7β-[2-Etherified oximino-2-(phenyl- or naphthylacetamido)] cephalosporins

ABSTRACT

The invention provides novel antibiotic compounds which are 7 beta -acylamidoceph-3-em-4-carboxylic acids, and non-toxic derivatives thereof characterized in that the acylamido group has the structure &lt;IMAGE&gt;   where R is a hydrogen atom or an organic group and Ra is an etherifying monovalent organic group linked to the oxygen atom through a carbon atom. The compounds are syn isomers or exist as mixtures containing at least 75% of the syn isomer. These antibiotic compounds possess high antibacterial activity against a range of gram positive and gram negative organisms coupled with particularly high stability to  beta -lactamases produced by various gram negative organisms. The invention is also concerned with the administration of the compounds.

CROSS REFERENCE TO RELATED APPLICATION

This is a division of application Ser. No. 587,065, filed June 16, 1975now U.S. Pat. No. 4,024,137, which is in turn a division of applicationSer. No. 304,524 filed Nov. 7, 1972, and now U.S. Pat. No. 3,971,778,which is in turn a continuation-in-part of application Ser. No. 252,666,filed May 12, 1972, and now abandoned.

This invention is concerned with improvements in or relating toantibiotics of the cephalosporin series.

The cephalosporin compounds referred to in this specification aregenerally named with reference to cepham (J. Amer. Chem. Soc. 1962, 843400). The term "cephem" refers to the basic cepham structure with onedouble bond.

As is well known, antibiotics of the cephalosporin series are7β-acylamido-ceph-3-em-4-carboxylic acids and their various non-toxicderivatives e.g. salts, esters, lactones (if such can be formed),amides, hydrates or the corresponding sulphoxides. These antibiotics maycontain various substituents particularly at the 3-position includingunsubstituted methyl and methyl groups substituted with a variety ofsubstituents as is described in the literature.

The new compounds of the present invention are characterized in thatsaid acylamido group of the cephalosporin antibiotic is an (α-etherifiedoximino) acylamido group, the compounds being syn isomers or mixtureswherein the syn isomeric form predominates.

According to one embodiment of the invention, therefore, we provide acompound selected from the group of 7β-acylamidoceph-3-em-4-carboxylicacids (and non-toxic derivatives thereof) characterized in that saidacylamido group has the structure: ##STR2## where R is a hydrogen atomor an organic group and R^(a) is an etherifying monovalent organic grouplinked to the oxygen atom through a carbon atom, said compound being asyn isomer or existing as a mixture containing at least 75% of the synisomer. Preferably, the mixtures of isomers contain at least 90% of thesyn isomer and not more than 10% of the anti isomer.

The compounds of the invention are defined as having the syn (cis)isomeric form as regards the configuration of the group OR^(a) withrespect to the carboxamido group. In this specification, the synconfiguration is structurally denoted thus: ##STR3## and the anticonfiguration thus: ##STR4## These configurations are assigned to thebasis of the work of Ahmad and Spencer (Can. J. Chem., 1961, 39, 1340).

The compounds of the invention may be defined by the formula: ##STR5##where R and R^(a) have the above-defined meanings, B is >S or >S→O and Zis a group in which 2 carbon atoms link the nuclear sulphur atom and thecarbon atom bearing the carboxylic acid group and which possesses Δ³unsaturation.

The term "non-toxic" as applied to the derivatives of the compounds ofthe invention means those derivatives which are physiologicallyacceptable in the dosage at which they are administered.

Salts which may be formed, where applicable, from the compoundsaccording to the invention include (a) inorganic base salts such asalkali metal, e.g. sodium and potassium, alkaline earth metal e.g.calcium, and organic base, e.g. procaine, phenylethylbenzylamine,dibenzylethylene diamine, ethanolamine, diethanolamine andN-methylglucosamine salts and (b) acid addition salts, e.g withhydrochloric, hydrobromic, sulphuric, nitric, phosphoric,toluene-p-sulphonic and methane sulphonic acids. These salts may also bein the form of resinates, formed e.g. with a polystyrene resincontaining amino, quaternary amino, or sulphonic acid groups, or a resincontaining carboxyl groups, e.g. a polyacrylic acid resin. The resin mayif desired be cross-linked, e.g. it may be a copolymer of styrene anddivinyl-benzene containing the appropriate groups. Additionally, thederivatives may be in the form of a chelate with a heavy metal such asiron or copper.

The compounds of the invention, including the non-toxic derivativesthereof, are characterized by their high antibacterial activity againsta range of gram-positive and gram-negative organisms coupled withparticularly high stability to β-lactamases produced by various gramnegative organisms.

Stability to β-lactamases may be assessed as compared with cephaloridinewhich may be arbitrarily defined as having a value of 1 with respect tothe particular organism.

The properties possessed by the compounds according to the inventionrender them useful in the treatment of a variety of diseases caused bypathogenic bacteria in human beings and animals.

Preferred cephalosporin compounds according to the invention may bedefined as compounds of the general formula ##STR6## (wherein R, R^(a)and B have the above defined meanings and P is an organic group) andnon-toxic derivatives thereof. In formula (II) B is preferably >S.

The invention also includes cephalosporin compounds not specificallyembraced by formula (II), e.g. 2-methyl and 2-methylene cephalosporins.

The group R^(a) in the above formulae may be any group having a carbonatom with one free valency so that forms the desired ether group withthe adjacent oxygen atom. The group R^(a) desirably contains not morethan 16 carbon atoms.

R^(a) may thus be, for example, an alkyl group containing 1-16 carbonatoms, particularly a lower alkyl goup containing 1-8 carbon atoms, e.g.a methyl, ethyl, n-propyl, iso-propyl, n-butyl, iso-butyl, sec-butyl,t-butyl, octyl or dodecyl group; an alkenyl group containing 2-16 carbonatoms, preferably 2-8 carbon atoms, e.g. a vinyl, allyl, isopropenyl, ordimethylallyl group; an alkynyl group containing 2-16 carbon atoms,preferably 2-8 carbon atoms, e.g. a propynyl group such as propargyl; acycloalkyl group containing 3-7 carbon atoms, e.g. a cyclopropyl,cyclopentyl or cyclohexyl group; a cycloalkenyl group containing 4-7carbon atoms, e.g. a cyclopentenyl, cyclohexenyl, cyclopentadienyl orcyclohexadienyl group; a carbocyclic aryl group e.g. a phenyl ornaphthyl group; a heterocyclic group, particularly one having a 5- or6-membered heterocyclic ring, containing at least one hetero atomselected from oxygen, nitrogen and sulphur, e.g. a pyridyl, pyrimidyl,furyl, thienyl, thiazolyl, thiadiazolyl, diazolyl, triazolyl,tetrazolyl, thiatriazolyl, oxazolyl, oxadiazolyl, benzimidazolyl,benzoxazolyl or purinyl group; or a carbocyclic or heterocyclic aryllower alkyl group in which the lower alkyl portion contains 1-4 carbonatoms, e.g. a benzyl, phenylethyl, diphenylmethyl, triphenylmethyl,thienylmethyl such as thien-2-ylmethyl, furylmethyl such as furfuryl,pyridylmethyl, or pyrrolylmethyl group.

In general R^(a) may be unsubstituted or may carry one or moresubstituents such as, for example, hydroxy; alkoxy, e.g. methoxy,ethoxy, n-propoxy or iso-propoxy, as in, for example, methoxymethyl or1-ethoxyethyl; aryloxy, e.g. phenoxy; aralkoxy, e.g. benzyloxy;mercapto; alkylthio, e.g. methylthio or ethylthio; arylthio;aralkylthio; amino as in, for example, 2-aminoethyl; substituted amino,e.g. methylamino, ethylamino or dimethylamino; halo, e.g. chloro orbromo, as in, for example, 2-bromoethyl; nitro; azido; carboxy;esterified carboxy, e.g. lower alkoxycarbonyl such as methoxycarbonyl orethoxycarbonyl, or benzyloxycarbonyl; formyl; acyl, e.g. acetyl,propionyl or benzoyl; acyloxy e.g. acetoxy, propionyloxy or pivaloyloxy;cyano; phthalimido; acylamido, e.g. acetamido or benzamido;alkoxycarbonylamino, e.g. methoxycarbonylamino or ethoxycarbonylamino;or aralkoxycarbonylamino, e.g. benzyloxycarbonylamino.

The group R in the above general formulae may be chosen from thefollowing list which is not included to be exhaustive:

(i) Hydrogen,

(ii) R^(u), where R^(u) is aryl (carbocyclic or heterocyclic),cycloalkyl, substituted aryl, substituted cycloalkyl, cycloalkadienyl,or a non-aromatic or mesionic group. Examples of this group includephenyl; naphthyl e.g. naphth-1-yl; phenyl or naphthyl substituted byhalo e.g. chloro or bromo as in o-chlorophenyl, hydroxy, lower alkyle.g. methyl, nitro, amino, lower alkylamino e.g. methylamino,diloweralkylamino e.g. dimethylamino, lower alkanoyl e.g. acetyl, loweralkanoylamido, lower alkoxy e.g. methoxy or ethoxy, or lower alkylthioe.g. methylthio; a 5- or 6-membered heterocyclic group containing atleast one hetero atom selected from S, N and O e.g. thien-2-yl,thien-3-yl, furyl such as fur-2-yl, pyridyl such as pyrid-3-yl,pyrrolyl, N-substituted pyrrolyl e.g. N-methylpyrrolyl orN-benzyloxymethylpyrrolyl, isothiazolyl, thiadiazolyl, oxadiazolyl, 3-or 4-isoxazolyl; substituted 3- or 4-isoxazolyl e.g.3-aryl-5-methylisoxazol-4-yl, the aryl group being e.g. phenyl orhalophenyl; fused heterocyclic groups containing at least one heteroatom selected from S, N and O, e.g. benzothienyl such asbenzothien-3-yl, benzofuryl, indolyl; cyclohexyl; cyclopentyl; sydnone;and cyclohexadienyl.

(iii) R^(u) (CH₂)_(m) Q_(n) (CH₂)_(p) where R^(u) has the above definedmeaning and m is 0 or an integer from 1 to 4, n is 0 or 1, p is aninteger from 1 to 4 and Q is S, O or NR wherein R is hydrogen or anorganic group e.g. alkyl such as methyl or aryl such as phenyl. Examplesof this group include methyl, ethyl or butyl substituted by the variousspecific R^(u) groups listed under (ii) e.g. benzyl and the appropriatesubstituted benzyl groups.

(iv) C_(n) H_(2n+1) wherein n is an integer from 1 to 7. The group maybe straight or branched and, if desired, may be interrupted by an oxygenor sulphur atom or the group NR wherein R is hydrogen or an organicgroup e.g. alkyl such as methyl or aryl such as phenyl; or besubstituted by a cyano, carboxy, alkoxycarbonyl, hydroxy orcarboxycarbonyl (HOOC.CO.) group or by a halogen atom. Examples of suchgroups include hexyl, heptyl, butylthiomethyl, cyanomethyl ortrihalomethyl.

(v) C_(n) H_(2n-1) where n is an integer from 2 to 7. The group may bestraight or branched and, if desired, may be interrupted by an oxygen orsulphur atom or the group NR wherein R is hydrogen or an organic groupe.g. alkyl such as methyl or aryl such as phenyl. An example of such agroup is vinyl or propenyl.

(vi) C_(n) H_(2n-3) where n is an integer from 2 to 7. An example ofsuch a group is ethynyl.

(vii) Miscellaneous carbon-linked organic groups including cyano, amidoand lower alkoxycarbonyl.

The 3-substituent P of the above compounds of formula II may be anyorganic group, the characterising feature of the invention being thenature of the 7-substituent. P may thus be a saturated or unsaturated,substituted or unsubstituted, organic group containing 1-20 carbonatoms. Preferred saturated organic groups include methyl and ethyl;preferred unsaturated organic groups include vinyl and substituted vinylgroups of the formula ##STR7## wherein R³ and R⁴, which may be the sameor different, are each hydrogen or a substituted or unsubstitutedaliphatic (e.g. alkyl, preferably C₁ -C₆ alkyl such as methyl, ethyl,iso-propyl, n-propyl etc.), C₅ -C₇ cycloaliphatic (e.g. cyclopentyl orcyclohexyl), C₇ -C₁₀ araliphatic (e.g. benzyl or phenylethyl), C₆ -C₁₂aromatic (e.g. phenyl or nitrophenyl) group, nitrile or loweralkoxycarbonyl.

When P is a substituted methyl group, it may be depicted by the formula

    --CH.sub.2 Y

wherein Y is an atom or group e.g. the residue of a nucleophile or aderivative of a residue of a nucleophile. Y may thus, for example, bederived from the wide range of nucleophilic substances characterised bypossessing a nucleophilic nitrogen, carbon, sulphur or oxygen atomdescribed widely in earlier patents and literature pertaining tocephalosporin chemistry. Examples of such nucleophiles include:

NITROGEN NUCLEOPHILES

Examples of nitrogen nucleophiles include tertiary aliphatic, aromatic,araliphatic and cyclic amines including trialkylamines, for example,triethylamine, pyridine bases such as pyridine and alkyl pyridines;heterocyclic amines having more than one heteroatom, at least oneheteroatom being nitrogen, such as pyrimidines, purines, pyridazines,pyrazines, pyrazoles, imidazoles, triazoles and thiazoles.

A preferred class of nitrogen nucleophile are those compounds of theformula: ##STR8## in which n is 0 or an integer from 1 to 5 and R^(d),which when n is from 2 to 5, may be the same or different, is analiphatic, e.g. lower alkyl such as methyl, ethyl, n-propyl, iso-propyletc; an aryl e.g. phenyl; an araliphatic, e.g. phenyl lower alkyl suchas benzyl, phenylethyl etc; or an alkoxymethyl e.g. methoxymethyl,ethoxymethyl, n-propoxymethyl, iso-propoxymethyl etc; or acyloxymethyle.g. alkanoyloxymethyl such as acetoxymethyl; formyl; carbamoyl; acyloxye.g. alkanoyloxy such as acetoxy; esterified carboxyl; alkoxy e.g.methoxy, ethoxy, n-propoxy, iso-propoxy etc; aryloxy e.g. phenoxy;aralkoxy e.g. benzyloxy; alkylthio e.g. methylthio, ethylthio; arylthio;aralkylthio; cyano; hydroxy; N-monoloweralkylcarbamoyl e.g.N-methylcarbamoyl, N-ethylcarbamoyl etc; N,N-diloweralkylcarbamoyl e.g.N,N-dimethylcarbamoyl, N,N-diethylcarbamoyl etc;N-(hydroxyloweralkyl)carbamoyl e.g. N-(hydroxymethyl)carbamoyl,N-(hydroxyethyl)carbamoyl etc; or carbamoylloweralkyl e.g.carbamoylmethyl, carbamoylethyl etc. group.

Another preferred class of nitrogen nucleophiles are azides e.g. alkalimetal azides such as sodium azide.

When the group Y is a derivative of a residue of a nucleophile it may bean amino group or an acylamido group. Compounds in which Y is amino maybe derived from the corresponding azide by reduction e.g. by catalytichydrogenation of the azide using a precious metal catalyst such aspalladium or platinum.

The amino group may be acylated to form a corresponding3-acylaminomethyl compound. The formation of such compounds may, forexample, be effected by any method suitable for acylating anaminocephalosporin e.g. reaction of the 3-aminomethyl compound with anacid chloride, acid anhydride or mixed anhydride or an acidcorresponding to the desired acyl group and another acid.

The 3-aminomethyl compounds may also be reacted with a substitutedisocyanate or isothiocyanate to yield urea or thiourea derivatives.

Other compounds in which Y is a derivative of a residue of a nucleophilemay be obtained by reacting 3-azidomethyl compounds with adipolarophile. Preferred classes of dipolarophiles include acetylenic,ethylenic and cyano dipolarophiles.

Acetylenic dipolarophiles may be shown as having the structure

    R.sup.1.C.tbd.C.R.sup.2

wherein R¹ and R² which may be the same or different are atoms orgroups.

In general we prefer that R¹ and preferably also R² should be of anelectronegative nature. Examples of such groups include cyano, CO₂ R³,COR³ (where R³ is for example, lower alkyl, aryl or lower aralkyl), andtrihalomethyl e.g. trifluoromethyl.

However, R¹ and preferably also R² could be electropositive e.g. alkoxyor alkylamino.

R¹ and R² may together form a ring system with the acetylenic group suchas, for example, in an aryne.

Where R¹ and R² are discrete atoms or groups which are identical asingle compound will result on reaction with the azido cephalosporin; ifthey are different one will in general obtain a mixture of positionisomers.

Ethylenic dipolarophiles may be shown as having the structure ##STR9##where R⁵, R⁶, R⁷ and R⁸ which may be the same or different are atoms orgroups. Although R⁵, R⁶, R⁷ and R⁸ may all be hydrogen, ethylene per se,like acetylene, reacts sluggishly with azido groups. R⁵ and R⁷ maytogether form a cyclic structure, e.g. a carbocyclic structure, with theethenoid group such that the double bond is strained. Examples ofethylenic dipolarophiles containing strained double bonds includenorbornenes, transcycloalkenes and acenaphthalene.

Further ethylenic dipolarophiles which may be used include compounds ofthe formula R⁵.R⁶. C ═ CR⁷.R⁸ where at least one of R⁵, R⁶, R⁷ and R⁸ isan electronegative group. R⁵ and R⁷ may thus be identicalelectronegative groups, R⁶ and R⁸ being other groups as desired. R⁶ andR⁸ may thus together form a ring system. Examples of such dipolarophilesinclude benzoquinone and nuclear substituted benzoquinones andmaleimide. Again all of R⁵, R⁶, R⁷ and R⁸ may be identicalelectronegative groups. Electronegative groups which may be used includethose listed under the section on acetylenic dipolarphiles and examplesof such compounds thus include dicyanoethylene and lower mono- anddi-alkoxycarbonyl ethylenes.

One or more of R⁵, R⁶, R⁷ and R⁸ may if desired be electropositive.

Cyano compounds, especially those which are activated by electronegativegroups, may function as cyano dipolarophiles. Examples of suchdipolarophiles include lower alkoxy carbonyl cyanides and cyanogen.

CARBON NUCLEOPHILES

Examples of "carbon nucleophiles" include inorganic cyanides, pyrrolesand substituted pyrroles, e.g. indoles, and compounds giving stabilisedcarbanions, for example, acetylenes and compounds having β-diketonegroups, for example acetoacetic and malonic esters andcyclohexane-1,3-diones or enamines, ynamines or enols.

The carbon nucleophile may thus give rise to cephalosporin compoundscharacterized by possessing a substituent at the 3-position in which acarbonyl group is linked to the cephalosporin nucleus through two carbonatoms. Such compounds may thus possess as the 3-substituent a group ofthe formula ##STR10## wherein R² and R³, which may be the same ordifferent, are selected from hydrogen, cyano, lower alkyl e.g. methyl orethyl, phenyl, substituted phenyl e.g. halo, lower alkyl, lower alkoxy,nitro, amino or lower alkylamino phenyl, lower alkoxycarbonyl, mono- ordi-aryl lower alkoxycarbonyl, lower alkylcarbonyl, aryl lower alkyl orC₅ or C₆ cycloalkyl and R⁴ is selected from hydrogen, lower alkyl e.g.methyl or ethyl, phenyl, substituted phenyl e.g. halo, lower alkyl,lower alkoxy, nitro, amino or lower alkylamino phenyl, aryl lower alkylor C₅ or C₆ cycloalkyl.

SULPHUR NUCLEOPHILES

Examples of "sulphur nucleophiles" include thiourea and aliphatic,aromatic, araliphatic, alicylic and heterocyclic substituted thioureas;dithiocarbamates; aromatic, aliphatic and cyclic thioamides, for examplethioacetamide and thiosemicarbazide; thiosulphates; thiols; thiophenols;thioacids, e.g. thiobenzoic acid or thiopicolinic acid; and dithioacids.

A preferred class of "sulphur nucleophile" includes those compounds ofthe formula: R¹ .S(O)_(n) H in which R¹ is an aliphatic e.g. lower alkylsuch as methyl, ethyl, n-propyl etc. group; an alicyclic e.g.cyclohexyl, cyclopentyl etc. group; an aromatic e.g. phenyl, naphthyletc. group; an araliphatic e.g. benzyl group; or a heterocyclic group,and n is 0, 1 or 2. A particularly preferred class of nucleophilesfalling within the above formula is that having the general formula; R⁶SH in which R⁶ is an aliphatic e.g. lower alkyl e.g. methyl, ethyl,n-propyl etc.; loweralkylcarbonyl e.g. acetyl araliphatic, e.g. phenyllower alkyl e.g. benzyl, phenylethyl etc. or substituted phenyl loweralkyl; alicyclic e.g. cycloalkyl e.g. cyclopentyl or cyclohexyl;aromatic e.g. phenyl or substituted phenyl or a 5- or 6-memberedheterocyclic group containing at least one of O, N and S e.g.thiadiazolyl, particularly 5-methyl-1,3,4-thiadiazol-2-yl or2-phenyl-1,3,4-oxadiazol-5-yl, diazolyl, triazolyl, tetrazolyl,particularly 1-methyltetrazol-5-yl or 1-ethyltetrazol-5-yl thiazolyl,thiatriazolyl, oxazolyl, oxadiazolyl, pyridyl and pyrimidyl, or asubstituted heterocyclic group, including such groups substituted by adivalent group to give a fused ring system, e.g. benzimidazolyl,benzoxazolyl, triazolopyridyl, benzothiazolyl, particularlynitrobenzothiazolyl and purinyl.

OXYGEN NUCLEOPHILES

Examples of oxygen nucleophiles include water, alcohols, for examplealkanols such as methanol, ethanol, propanol and butanol and loweralkanoic and alkenoic acids.

The term "oxygen nucleophile" thus includes compounds of the followingformula: R^(t) OH in which the group R^(t) may be lower alkyl (e.g.methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl etc.); loweralkenyl (e.g. allyl); lower alkynyl (e.g. propynyl, etc); lowercycloalkyl (e.g. cyclopropyl, cyclopentyl, cyclohexyl, etc); lowercycloalkyl lower alkyl (e.g. cyclopropylmethyl, cyclopentylmethyl,cyclohexylethyl etc); aryl (e.g. phenyl or naphthyl); aryl lower alkyl(e.g. benzyl); heterocyclic; heterocyclic lower alkyl (e.g. furfuryl) orany of these groups substituted by, for example, one or more of loweralkoxy (methoxy, ethoxy, etc.), lower alkylthio (methylthio, ethylthio,etc), halogen (chlorine, bromine, iodine or fluorine), lower alkyl(methyl, ethyl etc), nitro, hydroxy, acyloxy, carboxy, carbalkoxy, loweralkylcarbonyl, lower alkylsulphonyl, lower alkoxysulphonyl, amino, loweralkylamino or acylamino groups.

In the case in which water is the nucleophile there will be obtained3-hydroxymethyl cephalosporin compounds. Such compounds have the formula##STR11## where R and R^(a) have the above defined meanings. Compoundsof formula (A) and non-toxic derivatives thereof possess antibacterialactivity and it is of note that they may be metabolites of compounds ofgeneral formula II where B is >S and P is acetoxymethyl. Compounds offormula (A) may be acylated to form derivatives characterised bypossessing the group 3--CH₂.O.CO.R⁹ or 3--CH₂.O.CO.AR¹⁰ where A is O, Sor NH, R⁹ is methyl or an organic group having an atomic weight sum ofat least 16 and R¹⁰ is hydrogen or R⁹.

The group R⁹ CO-- or, R¹⁰ A.CO-- may be chosen from among the wide classof such groups described in the literature and may have up to 20 carbonatoms. The group R⁹ may thus be a hydrocarbon group or such a groupcarrying one or more substituent atoms or groups. The group R⁹ may thusbe chosen from the following list which is not intended to beexhaustive:-

(i) C_(n) H_(2n+1) where n is an integer from 1 to 7, e.g. 2 to 4. Thegroup may be straight or branched and, if desired, may be interrupted byan oxygen or sulphur atom or an imino group or substituted by cyano,carboxy, alkoxycarbonyl, hydroxy, carboxycarbonyl (HOOC.CO.), halogene.g. chlorine, bromine or iodine, or amino. Examples of such groupsinclude ethyl, propyl, isopropyl, n-butyl, t-butyl, sec. butyl and2-chloroethyl.

(ii) C_(n) H_(2n-1) where n is an integer from 2 to 7. The group may bestraight or branched and, if desired, may be interrupted by an oxygen orsulphur atom or an imino group. An example of such a group is vinyl orpropenyl.

(iii) R^(v), where R^(v) is aryl (carbocyclic or heterocyclic),cycloalkyl, substituted aryl and substituted cycloalkyl. Examples ofthis group include phenyl; substituted phenyl e.g. hydroxyphenyl,chlorophenyl, fluorophenyl, tolyl, nitrophenyl, aminophenyl,methoxyphenyl or methylthiophenyl; thien-2- and - 3-yl; pyridyl;cyclohexyl; cyclopentyl; cyclopropyl; sydnone; naphthyl; substitutednaphthyl e.g. 2-ethoxynaphthyl.

(iv) R^(v) (CH₂)_(m) where R^(v) has the meaning defined above under(iii) and m is an integer from 1 to 4. Examples of this group includemethyl, ethyl or butyl substituted by the various specific R^(v) groupslisted under (iii) e.g. benzyl and the appropriate substituted benzylgroups.

An important class of cephalosporin compounds are those possessing thegroup S-CH₂ Hal wherein Hal is chlorine, bromine or iodine. Suchcompounds may be primarily of value as intermediates of use in thepreparation of active cephalosporin compounds.

Important antibiotic compounds according to the invention by virtue oftheir generally broad spectrum antibiotic properties including activityagainst strains of Haemophilus influenzae coupled with stability toβ-lactamases produced by a variety of gram-negative organisms arecompounds of the general formula ##STR12## and non-toxic derivativesthereof. In formula (B) R^(u) is phenyl; naphthyl; thienyl; furyl;benzothienyl, benzofuryl or pyridyl or any of these groups substitutedby halo (chloro, bromo, iodo or fluoro), hydroxy, lower alkyl, nitro,amino, loweralkylamino, dilower-alkylamino, lower alkanoyl, loweralkanoylamido, lower alkoxy, lower alkylthio or carbamoyl; R^(b) islower alkyl, cycloalkyl (C₃₋₇), or aryl (carbocyclic e.g. phenyl orheterocyclic e.g. thienyl or furyl) lower alkyl or any of these groupssubstituted by hydroxy, carboxy, esterified carboxy, amido, cyano,alkanoyl, amino, substituted amino, nitro halogen or lower alkoxy; andthe group Y is selected from

(a) acetoxy;

(b) the residue of a nitrogen nucleophile of the formula ##STR13##(wherein R^(d) and n have the above defined meanings);- in this case the4-position group of the compound of formula (B) will be present as --CO₂⁻ ;

(c) the group --SW wherein W is thiadiazolyl preferably5-methyl-1,3,4-thiadiazol-2-yl, diazolyl, triazolyl, tetrazolyl,preferably 1-methyltetrazol-5-yl and 1-ethyltetrazol-5-yl, thiazolyl,thiatriazolyl, oxazolyl, oxadiazolyl, benzimidazolyl, benzoxazolyl,triazolopyridyl, benzothiazolyl, preferably nitrobenzothiazolyl,purinyl, pyridyl or pyrimidyl;

(d) lower (C₁ -C₄) alkylthio;

(e) the group --O.CO.R⁹ wherein R⁹ is C₂ -C₄ alkyl or C₂ -C₄ alkenyl;

(f) the group --O.CO.NH.(CH₂)_(m) D wherein m is an integer of from 1-4and D is chlorine, bromine, iodine or fluorine; and

(g) azido

Particularly important compounds of general formula (B) by virtue oftheir broad spectrum antibiotic properties, including high activityagainst strains of Pseudomonas pyocyanea are those having the generalformula ##STR14## (wherein R^(x) is phenyl; naphthyl; thienyl; furyl;benzothienyl or benzofuryl and R^(c) is C₂ -C₄ alkyl, cyclopentyl,phenyl, benzyl, phenethyl, thienylmethyl, furylmethyl) and non-toxicderivatives thereof.

Important compounds falling within general formula (C) include thefollowing compounds in their syn isomeric form:-

3-acetoxymethyl-7β-(2-ethoxyimino-2-phenylacetamido)-ceph-3-em-4-carboxylicacid;

3-acetoxymethyl-7β-[2-t-butoxyimino-2-(2-thienyl)acetamido]ceph-3-em-4-carboxylicacid;

3-acetoxymethyl-7β-[2-(2-thienyl)methoxyimino-2-(2-thienyl)acetamido]ceph-3-em-4-carboxylicacid;

3-acetoxymethyl-7β-[2-t-butoxyimino-2-(2-furyl)acetamido]ceph-3-em-4-carboxylicacid;

3-acetoxymethyl-7β-[2-benzyloxyimino-2-(2-thienyl)acetamido]ceph-3-em-4-carboxylic acid;

3-acetoxymethyl-7β-[2-t-butoxyimino-2-(1-naphthyl)acetamido]ceph-3-em-4-carboxylicacid; and

3-acetoxymethyl-7β-[2-n-butoxyimino-2-(2-thienyl)acetamido]ceph-3-em-4-carboxylicacid;

3-acetoxymethyl-7β-(2-phenoxyimino-2-phenylacetamido)ceph-3-em-4-carboxylicacid;

3-acetoxymethyl-7β-[2-phenoxyimino-2-(2-furyl)acetamido]ceph-3-em-4-carboxylicacid;

3-acetoxymethyl-7β-[2-phenoxyimino-2-(2-thienyl)acetamido]ceph-3-em-4-carboxylicacid;

3-acetoxymethyl-7β-[2-cyclopentyloxyimino-2-(2-furyl)acetamido]ceph-3-em-4-carboxylicacid;

3-acetoxymethyl-7β-[2-cyclopentyloxyimino-2-(2-thienyl)acetamido]ceph-3-em-4-carboxylicacid;

3-acetoxymethyl-7β-(2-cyclopentyloxyimino-2-phenyl-acetamido)ceph-3-em-4-carboxylicacid;

especially as their sodium, potassium or diethanolamine salts.

An important group of compounds falling within general formula (B) byvirtue of their broad spectrum antibiotic properties including highactivity against strains of Haemophilus influenzae are those having thegeneral formula ##STR15## [wherein R^(x) and R^(b) are as defined aboveand T is acetoxy, azido, the residue of a nitrogen nucleophile of theformula ##STR16## (wherein R^(d) and n have the above defined meanings)or the group --O.CO.R⁹ wherein R⁹ is C₂ -C₄ alkyl, C₂ -C₄ alkenyl orphenyl] and non-toxic derivatives thereof.

A further important group of compounds falling within general formula(B) by virtue of their broad spectrum antibiotic properties coupled withsignificant absorption on oral administration as evidenced by aminaltests are those having the general formula ##STR17## (wherein R^(x) andR^(b) have the meanings defined above and V is lower (C₁ -C₄) alkylthio,C₂ -C₄ alkanoyl or C₂ -C₄ alkenoyl) and non-toxic derivatives thereof.

A still further important group of compounds falling within generalformula (B) which possess a very high degree of activity against avariety of gram positive and gram negative organisms coupled with highstability to β-lactamases produced by a variety of organisms are thosehaving the general formula ##STR18## [wherein R^(x) is as defined abovefor formula (C)] and non-toxic derivatives thereof. A particularlyimportant compound of formula (F) is3-acetoxymethyl-7β-(2-methoxyimino-2-phenylacetamido)ceph-3-em-4-carboxylicacid (syn-isomer), especially as its sodium or potassium salt.

PREPARATION

The compounds according to the invention may be prepared by anyconvenient method. According to one embodiment of the invention weprovide a process for the preparation of a compound of the formula##STR19## (wherein R is a hydrogen atom or an organic group, R^(a) is anetherifying monovalent organic group linked to the oxygen atom through acarbon atom, B is >S or >S→O and Z is a group in which 2 carbon atomslink the nuclear sulphur atom and the carbon atom bearing the carboxylicacid group and which possesses Δ³ unsaturation) and derivatives thereof,which comprises either (A) condensing a compound of the formula##STR20## (wherein B and Z have the above defined meanings and R¹⁰ ishydrogen or a carboxyl blocking group) with an acylating agent,advantageously the syn isomer, corresponding to the acid ##STR21##(wherein R and R^(a) have the above defined meanings) or with anacylating agent corresponding to an acid which is a precursor for theacid IV; or (B) reacting a compound of the formula ##STR22## (wherein B,Z and R¹⁰ have the above defined meaning except that R¹⁰ is nothydrogen) with an acid, or precursor, of formula IV; or (C), where Z isthe group ##STR23## (wherein Y is the residue of a nucleophile or aderivative of the residue of a nucleophile and the dotted line bridgingthe 2,3 and 4 positions indicates that the compound may be a ceph-2-emor a ceph-3-em compound) reacting a compound of the formula ##STR24##(wherein Acyl is the group ##STR25## or a precursor therefor; B, R^(a),R¹⁰ and the dotted line have the above meanings and Y¹ is a replaceableresidue of a nucleophile) with a nucleophile whereafter, if necessaryand desired in each instance, any of the following reactions (D) arecarried out (i) conversion of a precursor for the ##STR26## group intothat said group (ii) conversion of a Δ² isomer into the desired Δ³isomer (iii) removal of any carboxyl blocking groups (iv) reduction of acompound in which Z is >S→O to form the desired Z= >S compound (v)reduction of a compound in which Y is azide to form a 3-aminomethylcompound and, if required, acylation of the resulting amino group toform a corresponding 3-acylaminomethyl compound (vi) reaction of acompound in which Y is azide with a dipolarophile to form a compoundhaving a polyazole ring linked to the 3-methylene group (vii)deacylation of a compound in which Y is an acyloxy group to form a3-hydroxymethyl compound and (viii) acylation of a compound in which Yis hydroxy to form a 3-acyloxymethyl or 3-carbamoyloxymethyl compoundand (E) recovering the desired compound of formula (I), after separationof isomers if necessary.

Salts of the compounds according to the invention may be formed in anyconvenient way. For example base salts may be formed by reaction of thecephalosporin acid with sodium or potassium 2-ethylhexanoate.

In practice it is convenient to condense an acylating agentcorresponding to the acid ##STR27## where R and R^(a) have the abovedefined meanings, with an amino compound ##STR28## [where Z and B havethe above defined meanings and R¹⁰ is hydrogen or a carboxyl blockinggroup e.g. the residue of an ester-forming alcohol (aliphatic oraraliphatic), phenol, silanol, stannanol or acid] the condensation, ifdesired, being effected in the presence of a condensation agent, andbeing followed, if necessary, by removal of the group R¹⁰.

In the case of the preparation of the preferred cephalosporin compoundsof formula (II) above, the amino compound (III) may have the formula##STR29## wherein R¹⁰, B and P have the above defined meanings. Theremay also be used a derivative of the amino compounds such as a salt e.g.a tosylate, or an N-silyl derivative.

The compounds of formula I may thus be prepared by employing as theacylating agent an acid halide, particularly an acid chloride orbromide. The acylation may be effected at temperatures of from -50° to+50° C, preferably -20° to +30° C. The acylating agent may be preparedby reacting the acid VII or a salt thereof with a halogenating agente.g. phosphorus pentachloride, thionyl chloride or oxalyl chloride. Useof oxalyl chloride with the sodium or potassium salt of the acid (VII)is preferred since under these conditions isomerisation is minimal. Theacylation may be effected in aqueous or non-aqueous media and suitablemedia include an aqueous ketone such as aqueous acetone, an ester e.g.ethyl acetate, or an amide e.g. dimethylacetamide, or a nitrile e.g.acetonitrile, or mixtures thereof.

Acylation with an acid halide may be effected in the presence of an acidbinding agent e.g. a tertiary amine (e.g. triethylamine ordimethylaniline), an inorganic base (e.g. calcium carbonate or sodiumbicarbonate) or an oxirane, which binds hydrogen halide liberated in theacylation reaction. The oxirane is preferably a lower-1,2-alkylene oxidee.g. ethylene oxide or propylene oxide.

When using the free acid form of a compound of formula (VII), suitablecondensing agents for use in the preparation of the compounds accordingto the invention include carbodiimides, for example N,N'-diethyl-,dipropyl- or diisopropylcarbodiimide, N,N'-dicyclohexylcarbodiimide, orN-ethyl-N'-γ-dimethylaminopropylcarbodiimide; a suitable carbonylcompound, for example carbonyldiimidazole; or an isoxazolinium salt, forexample, N-ethyl-5-phenylisoxazolinium-3'-sulphonate andN-t-butyl-5-methylisoxazolinium perchlorate. The condensation reactionis desirably effected in an anhydrous reaction medium, e.g. methylenechloride, dimethylformamide or acetonitrile.

Alternatively, acylation may be effected with other amide-formingderivatives of the free acid such as, for example, a symmetricalanhydride or mixed anhydride, e.g. with pivalic acid or formed with ahaloformate, e.g. a lower alkylhaloformate. The mixed or symmetricalanhydrides may be generated in situ. For example, a mixed anhydride maybe generated using N-ethoxycarbonyl-2-ethoxy-1,2-dihydroquinoline. Mixedanhydrides may also be formed with phosphorus acids (for examplephosphoric or phosphorous acids), sulphuric acid or aliphatic oraromatic sulphonic acids (for example p-toluene sulphonic acid). Anotherconvenient acylating agent is an activated ester e.g. a compound of theformula ##STR30## where L, is for example, azide, oxysuccinimide,oxybenztriazole, pentachlorophenoxy or p-nitrophenoxy group.

Alternatively the compound of formula (I) may be prepared from acompound of formula ##STR31## (where B, Z and R¹⁰ have the above definedmeanings except that R¹⁰ is not hydrogen) by reaction with an acid, orprecursor, of formula VII and subsequently removing the group R¹⁰ (seefor example Belgian Pat. No. 760,494).

The reaction of the compound of formula (III) or (V) may be carried outtowards the end of a preparative sequence, the only additional reactionsbeing deprotection reactions and purifications.

If desired, one can first prepare a compound of formula ##STR32## (whereR, R¹⁰, B and Z have the above defined meanings) and then effectreaction of the compound of formula (X) with R^(a) O.NH₂ (R^(a) havingthe above defined meaning), followed, if necessary by removal of thegroup R¹⁰. The reaction product may be separated to give the requiredsyn isomer before or after removal of R¹⁰.

The useful precursor of the desired ##STR33## group is the corresponding2-hydroxyiminoacyl group ##STR34## since this may readily be convertedto the desired group by etherification. Thus compounds of formula (I)may be prepared by reacting a compound of formula ##STR35## wherein R,R¹⁰, B and Z are as hereinbefore defined, with an etherifying agentserving to introduce the group R^(a) and subsequently if necessary anddesired carrying out any of reactions D(ii)-(viii) described above andrecovering the desired compound of formula (I), after separation ofisomers if necessary.

The etherifying agent may be, for example, an organic halide orsulphate, or a sulphonate such as tosylate. Other etherifying agentsinclude diazoalkanes, e.g. diazomethane or diazoethane, alkylfluorosulphonates, e.g. methyl fluorosulphonate, and alkyloxoniumtetrafluoroborates, e.g. a trialkyloxonium tetrafluoroborate such astriethyloxonium tetrafluoroborate and diphenyliodonium bromide.Etherifications using a diazo compound, fluorosulphonate ortetrafluoroborate may require assistance, e.g. with a Lewis acid such asBF₃.

One may prepare compounds of formula (I) wherein R is an activatinggroup such as cyano or 2- or 4-pyridyl by a technique involvingnitrosation and etherification of the resulting oxime. Thus a compoundpossessing the acylamido group ##STR36## may be nitrosated using, forexample, nitrous acid (which may be prepared in situ by reaction of analkali metal nitrite with a weak acid e.g. acetic acid), nitrosylchloride, or an organic nitrosating agent e.g. an alkyl, cycloalkyl, oraralkyl nitrite. In the case of nitrosation of a compound containing thegroup ##STR37## decarboxylation will occur. Separation of syn andanti-isomers may be necessary after the nitrosation or etherificationreaction.

If desired the replacement of one P group by another and preferred Pgroup may be carried out after acylation of the 7-amino or 7-isocyanatocompound has taken place. In particular when P is the group

    --CH.sub.2 Y

where Y has the above defined meaning the Y group may be introduced bymethods described in the literature. Thus compounds in which Y is ahalogen atom, an ether group, or a thioether group may be prepared asdescribed in Belgian Pat. Nos. 719,711; 719,710; 734,532 and 734,533.Compounds wherein Y is the residue of a nucleophile may also be preparedby the reaction of a 3-acetoxymethyl cephalosporin compound with anucleophile, for example, pyridine or other tertiary amine as describedin British Pat. No. 912,541; a sulphur-linking, nitrogen-linking orinorganic nucleophile as described in British Pat. No. 1,012,943; asulphur-linking nucleophile as described in British Pat. Nos. 1,059,562,1,101,423 and 1,206,305; or a nitrogen-linking nucleophile as describedin British Pat. Nos. 1,030,630, 1,082,943 and 1,082,962.

Compounds in which Y is a derivative of a residue of a nucleophile, e.g.where Y is an amino or acylamido group derived from an azido group maybe prepared as described in British Pat. Nos. 1,057,883 and 1,211,694these patents further describing the reaction of compounds in which Y isazido with a dipolarophile. Compounds of the invention wherein Y is theresidue of a nucleophile may also be prepared by the reaction of a3-halomethyl-cephalosporin with any of the nucleophiles disclosed in theabove references, such a process being described in Belgian Pat. No.719,711. Where Y is a hydroxy group the compound may be prepared by themethods described in British Pat. No. 1,121,308.

Compounds having a vinyl or substituted vinyl group as 3-positionsubstituent may be obtained by the method described in Belgian Pat. No.761,897.

Where Y is a halogen (i.e. chlorine, bromine or iodine) ceph-3-emstarting compounds may be prepared by halogenation of a7β-acylamido-3-methylceph-3-em-4-carboxylic acid ester 1β-oxide followedby reduction of the 1β-oxide group later in the sequence as described inBelgian Pat. No. 755,256.

The corresponding ceph-2-em compounds may be prepared by the method ofDutch published Pat. application No. 6902013 by reaction of aceph-2-em-3-methyl compound with N-bromo-succinimide to yield theceph-2-em-3-bromomethyl compound.

Where Y is a hydrogen atom the compound may be prepared by the methoddescribed in British Pat. No. 957,569 or from a penicillin compound bythe method described in United States Patent Specification No. 3,275,626and Belgian Pat. Nos. 747,119 and 747,120.

Cephalosporin compounds possessing an acyloxymethyl group as 3-positionsubstituent may be prepared by any convenient method e.g. they may beprepared from a cephalosporin having a 3--CH₂ Y group where Y = OH orthe residue of the acid HY which has a pKa of not more than 4.0 andpreferably not more than 3.5 (as measured in water at 25° C).

The group Y may be a chlorine, bromine or iodine atom, formyloxy or anacetoxy group having at least one electron-withdrawing substituent onthe α-carbon atom or a nuclear substituted benzoyloxy group, the nuclearsubstituent being of the electron-withdrawing type as described inBritish Pat. No. 1,241,657 and the nucleophilic displacement reaction tointroduce the desired 3-position substituent may be carried out asdescribed in our aforesaid British Pat. No. 1,241,657.

Alternatively where Y is hydroxy the desired 3-acyloxymethylcephalosporin may be obtained by acylation analogous with that describedin British Pat. No. 1,141,293, which patent describes a process for thepreparation of a Δ³ -cephalosporin having a 3-acyloxymethyl substituentfrom a corresponding 3-hydroxymethyl analogue which comprisesaralkylating the 4-carboxy group, acylating the 3-hydroxymethyl group ofthe protected compound and subsequently removing the aralkyl group.

The acylation may be carried out by any convenient method, using forexample an acid chloride, acid anhydride or a mixed acid anhydride asthe acylating agent, preferably in the presence of an acid bindingagent, for example an organic base such as pyridine or a lower alkyleneoxide such as ethylene oxide or propylene oxide, and carrying out thereaction in solution in an inert anhydrous solvent, for examplemethylene chloride. Alternatively the acylation may be carried out inaqueous acetone/sodium bicarbonate solution. The preferred acylatingagent is the acid chloride.

The acylation reaction should be effected as rapidly as possible, sinceunder the conditions of the acylation rearrangement to the Δ²-derivative can occur, particularly when an aroyloxy group is beingintroduced at the exocyclic methylene group at the 3-position.

Compounds of the formula III may be employed as esters; those of formulaV are esters. One may also use the free amino acid or an acid additionsalt of the free amino acid or ester thereof. Salts which may be usedinclude acid addition salts e.g. with hydrochloric, hydrobromic,sulphuric, nitric, phosphoric, toluene-p-sulphonic and methane sulphonicacids.

The ester may be formed with an alcohol, phenol, silanol or stannanolhaving up to 20 carbon atoms which may readily be split off at a laterstage of the overall reaction.

Any esterifying group substituting the 4-carboxyl group of a compound offormula (III), (V) or (X) is preferably formed with an alcohol(aliphatic or araliphatic), phenol, silanol, stannanol or acid which mayreadily be split off at a later stage of the reaction.

Suitable esters thus include compounds containing as ester group a groupselected from the following list which is not intended to be anexhaustive list of possible ester groups.

(i) --COOCR^(f) R^(g) R^(h) wherein at least one of R^(f), R^(g) andR^(h) is an electron-donor e.g. p-methoxyphenyl, 2,4,6-trimethylphenyl,9-anthryl, methoxy, acetoxy, or fur-2-yl. The remaining R^(f), R^(g) andR^(h) groups may be hydrogen or organic substituting groups. Suitableester groups of this type include p-methoxybenzyloxycarbonyl and2,4,6-trimethylbenzyloxy carbonyl.

(ii) --COOCR^(f) R^(g) R^(h) wherein at least one of R^(f), R^(g) andR^(h) is an electron-attracting group e.g. benzoyl, p-nitrophenyl,4-pyridyl, trichloromethyl, tribromomethyl, iodomethyl, cyanomethyl,ethoxycarbonylmethyl, arylsulphonylmethyl, 2-dimethylsulphoniumethyl,o-nitrophenyl or cyano. The remaining R^(f), R^(g), and R^(h) groups maybe hydrogen or organic substituting groups. Suitable esters of this typeinclude benzoylmethoxycarbonyl, p-nitrobenzyloxycarbonyl,4-pyridylmethoxycarbonyl, 2,2,2-trichloroethoxycarbonyl and2,2,2-tribromoethoxycarbonyl.

(iii) --COOCR^(f) R^(g) R^(h) wherein at least one of R^(f), R^(g) andR^(h) are hydrocarbon such as alkyl e.g. methyl or ethyl, or aryl e.g.phenyl and the remaining R^(f), R^(g) and R^(h) group, if there is one,is hydrogen. Suitable esters of this type include t-butyloxycarbonyl,t-amyloxycarbonyl, diphenylmethoxycarbonyl and triphenylmethoxycarbonyl.

(iv) --COOR^(i) wherein R^(i) is adamantyl, 2-benzyloxyphenyl,4-methylthiophenyl, tetrahydrofur-2-yl or tetrahydropyran-2-yl.

(v) Silyloxycarbonyl groups obtained by reaction of a carboxyl groupwith a derivative of a silanol. The derivative of a silanol isconveniently a halosilane or a silazane of the formula R¹¹ ₃ SiD; R¹¹ ₂SiD₂ ; R¹¹ ₃ Si.NR¹¹ ₂ ; R¹¹ ₃ Si.NH.SiR¹¹ ₃ ; R¹¹ ₃ Si.NH.COR¹¹ ; R¹¹ ₃Si.NH.CO.NH.SiR¹¹ ₃ ; R¹¹ NH.CO.NR¹¹.SiR¹¹ ₃ ; or R¹¹ C(OSir¹¹ ₃):NSiR¹¹ ₃ where D is a halogen and the various groups R¹¹, which can bethe same or different, represent hydrogen atoms or alkyl, e.g. methyl,ethyl, n-propyl, iso-propyl; aryl, e.g. phenyl; or aralkyl e.g. benzylgroups. Preferred derivatives of silanols are silyl chlorides such asfor example trimethylchlorosilane and dimethyldichlorosilane.

The carboxyl group may be regenerated from an ester by any of the usualmethods, for example, acid- and base-catalysed hydrolysis is generallyapplicable, as well as enzymically-catalysed hydrolyses; however,aqueous mixtures may be poor solvents for these compounds and they maycause isomerizations, rearrangements, side-reactions, and generaldestruction, so that special methods may be desirable.

Five suitable methods of deesterification are

(1) REACTIONS WITH LEWIS ACIDS

Suitable Lewis acids for reaction with the esters includetrifluoroacetic acid, formic acid, hydrochloric acid in acetic acid,zinc bromide in benzene and aqueous solutions or suspensions of mercuriccompounds. The reaction with the Lewis acid may be facilitated byaddition of a nucleophile such as anisole.

(2) REDUCTION

Suitable systems for effecting reduction are zinc/acetic acid,zinc/formic acid, zinc/lower alcohol, zinc/pyridine, palladised-charcoaland hydrogen, and sodium and liquid ammonia.

(3) ATTACK BY NUCLEOPHILES

Suitable nucleophiles are those containing a nucleophilic oxygen orsulphur atom for example alcohols, mercaptans and water.

(4) Oxidative methods, for example, those which involve the use ofhydrogen peroxide and acetic acid.

(5) IRRADIATION

Where at the end of a given preparative sequence compounds are obtainedwherein B is >S→O and a compound is desired in which B is >S conversionto a sulphide may for example, be effected by reduction of thecorresponding acyloxysulphonium or alkyloxysulphonium salt prepared insitu by reaction with e.g. acetyl chloride in the case of anacetoxysulphonium salt, reduction being effected by, for example, sodiumdithionite or by iodide ion as in a solution of potassium iodide in awater miscible solvent e.g. acetic acid, tetrahydrofuran, dioxan,dimethylformamide or dimethylacetamide. The reaction may be effected ata temperature of -20° to +50° C.

Alternatively, reduction of the 1-sulphinyl group may be effected byphosphorus trichloride or tribromide in solvents such as methylenechloride, dimethylformamide or tetrahydrofuran, preferably at atemperature of -20° C to +50° C.

Where the resultant compound is a ceph-2-em-4-ester the desiredceph-3-em compound may be obtained by treatment of the former with abase.

The acid IV to which the acylating agent corresponds may be obtained byreacting a glyoxylic acid of formula

    R.CO.COOH

(where R has the above defined meaning) or an ester thereof with R^(a)O.NH₂ (R^(a) having the above defined meaning).

The resulting acid or ester may then be separated into its syn and antiisomers e.g. by crystallisation, chromatography or distillation,followed when necessary by hydrolysis of the ester.

Separation of the syn and anti components of an ester derivative of anα(-etherified oximino)carboxylic acid existing as a mixture of the synand anti isomers may be effected by selective hydrolysis of the esterunder basic conditions, since the less sterically hindered anti isomertends to saponify more rapidly and may thus be removed as the free acid,leaving purified syn ester. The separated syn ester may then beconverted to a corresponding acylating agent as desired. This process asdescribed in greater detail in copending Application Serial No. ofJanice Bradshaw and Godfrey Basil Webb filed on even date herewith.

The acid (IV) may also be prepared by carrying out an O-alkylation orO-arylation type of reaction on a compound of the formula ##STR38## i.e.an 2-hydroximino acid, or more preferably on an ester of such an2-hydroximino acid. The desired reaction may be achieved with an organichalide, sulphate or sulphonate, e.g. a compound of formula R^(a) J whereR^(a) has the above-defined meaning and J is halogen, sulphate or asulphonate such as tosylate. Alternatively the 2-hydroximino acid or anester thereof may be reacted with a diazoalkane, e.g. diazomethane, analkyl fluorosulphonate, e.g. methyl fluorosulphonate, or an alkyloxoniumtetrafluoroborate, e.g. a trialkyloxonium tetrafluoroborate such astrimethyloxonium tetrafluoroborate to give the required alkoxyimino acid(VII) or an ester thereof, or with diphenyliodonium bromide to give therequired phenoxyimino acid (VII). Such reactions with a diazo compound,fluorosulphonate or tetrafluoroborate may require assistance, e.g. witha Lewis acid such as BF₃.

When converting the acid (IV) to a corresponding acylating agent it willbe appreciated that any amino groups present in R or R^(a) shoulddesirably be protected to avoid undesirable side reactions; similarprotection of amino groups is also desirable when reacting theconsequent acylating agent with a compound of formula (III) or (V).

Syn and anti isomers may be distinguished by appropriate techniques,e.g. by their ultraviolet spectra, by thin layer or paper chromatographyor by their nuclear magnetic resonance spectra. For example, for DMSO-d₆solution compounds of Formula I exhibit the doublet for the amide NH ata lower field for the syn isomers than for the anti-isomers. Thesefactors may be employed in monitoring reactions.

The antibacterial compounds according to the invention may be formulatedfor administration in any convenient way, by analogy with otherantibiotics and the invention therefore includes within its scope apharmaceutical composition comprising an antibacterial compound offormula I or a non-toxic derivative e.g. salt thereof (as hereindefined) adapted for use in human or veterinary medicine. Suchcompositions may be presented for use in conventional manner with theaid of any necessary pharmaceutical carriers or excipient.

The antibacterial compounds according to the invention may be formulatedfor injection and may be presented in unit dose form in ampoules, or inmultidose containers with an added preservative. The compositions maytake such forms as suspensions, solutions, emulsions in oily or aqueousvehicles, and may contain formulatory agents such as suspending,stabilising and/or dispersing agents. Alternatively the activeingredient may be in powder form for reconstitution with a suitablevehicle, e.g. sterile, pyrogen-free water, before use.

The compositions may be presented in a form suitable for absorption bythe gastro-intestinal tract. Tablets and capsules for oraladministration may be in unit dose presentation form, and may containconventional excipients such as binding agents, for example, syrup,acacia, gelatin, sorbitol, tragacanth, or polyvinyl-pyrollidone;fillers, for example lactose, sugar, maize-starch, calcium phosphate,sorbitol or glycine; lubricants, for example, magnesium stearate, talc,polyethylene glycol, silica; disintegrants, for example, potato starchor acceptable wetting agents such as sodium lauryl sulphate. The tabletsmay be coated according to methods well known in the art. Oral liquidpreparation may be in the form of aqueous or oily suspensions,solutions, emulsions, syrups, elixirs, etc. or may be presented as a dryproduct, for reconstitution with water or other suitable vehicle beforeuse. Such liquid preparations may contain conventional additives such assuspending agents, for example, sorbitol syrup, methyl cellulose,glucose/sugar syrup, gelatin, hydroxyethylcellulose, carboxymethylcellulose, aluminium stearate gel or hydrogenated edible fats,emulsifying agents, for example, lecithin, sorbitan monooleate oracacia; non-aqueous vehicles which may include edible oils, for example,almond oil, fractionated coconut oil, oily esters, propylene glycol, orethyl alcohol; preservatives, for example, methyl or propylp-hydroxybenzoates or sorbic acid. Suppositories will containconventional suppository bases, e.g. cocoa butter or other glyceride.

The composition may also be prepared in suitable forms for absorptionthrough the mucous membranes of the nose and throat or bronchial tissuesand may conveniently take the form of powder or liquid sprays orinhalants, lozenges, throat paints etc. For medication of the eyes orears, the preparations may be presented as individual capsules, inliquid or semi-liquid form, or may be used as drops etc. Topicalapplications may be formulated in hydrophobic or hydrophilic bases asointments, creams, lotions, paints, powders etc.

For veterinary medicine the composition, may, for example, be formulatedas an intramammary preparation in either long acting or quick-releasebases.

The compositions may contain from 0.1% upwards, preferably from 10-60%of the active material, depending on the method of administration. Wherethe compositions comprise dosage units, each unit will preferablycontain 50-500 mg. of the active ingredient. The dosage as employed foradult human treatment will preferably range from 100-3000 mg. forinstance 1500 mg per day, depending on the route and frequency ofadministration.

The compounds according to the invention may be administered incombination with other therapeutic agents such as antibiotics, forexample other cephalosporins, the penicillins or tetracyclines.

The following examples illustrate the invention.

PREPARATION 1 2-Methoxyiminophenylacetic acids (syn- and antiisomers)

A solution of sodium (5 g.) in dry methanol (100 ml) was added to asolution of 0-methylhydroxylamine hydrochloride (15 g.) in dry methanol(100 ml) until neutral to phenolphthalein. The precipitated sodiumchloride was removed by filtration, and the filtrate added to a solutionof phenylglyoxylic acid (25 g.) in dry methanol (100 ml). The solutionwas refluxed for 2 hours, cooled, and evaporated to an oil, which wasdissolved in ether (200 ml), refiltered and evaporated to an oil (32.9g.). This was crystallised from petroleum spirit, (bp. 60°-80°)producing a white solid (19.61 g.) and oil (3.9 g.).

The solid (17.8 g.) and the oil (3.9 g.) were combined (21.7 g.) andmethylated with ethereal diazomethane, producing an oil (24.2 g.). Thiswas purified by chromatography on silica gel (600 g.), producingsyn-methyl 2-methoxyiminophenylacetate as an oil (13.6 g. 55%), λ_(max).(EtOH) 259 nm (ε 10,400) and anti-methyl 2-methoxyiminophenylacetate,the slower component, as a solid (8.7 g.; 35%), m.p. 54°, λ_(max).(EtOH) 251 nm (ε 7,260).

Methyl 2-methoxyiminophenylacetate (anti-isomer) (8.7 g.) was dissolvedin methanol (100 ml) and 2N-sodium hydroxide solution (22 ml.) wasadded. The solution was stirred at room temperature for 1 hour, and thepH adjusted to 7 with 2N-hydrochloric acid. Methanol was removed byevaporation, water (150 ml.) was added, and the solution acidified to pH1.5 with 2N-hydrochloric acid. The mixture was extracted with ethylacetate (3 × 100 ml), the organic extracts were combined, dried andevaporated to give a solid (6.74 g.) which was crystallised frompetroleum spirit (b.pt. 60°-80°): benzene, producinganti-2-methoxyiminophenylacetic acid (4.84 g.), m.p. 103°-104°, γ_(max).(EtOH) 248 nm (ε 7,010). τ (CDCl₃) values include 2.64 (Ph), 5.92 (CH₃).

Methyl 2-methoxyiminophenylacetate (syn-isomer) 3.6 g.) was hydrolysedin a similar manner, but the hydrolysis mixture was stirred for 40 hoursat room temperature. The white solid (11.13 g.) formed was crystallisedfrom petroleum spirit (b.pt. 60°-80°); benzene producingsyn-2-methoxyiminophenylacetic acid as a white solid (10.02 g.). m.p.96°-97°, λ_(max). (EtOH) 255 nm, (ε 13,200), (CDCl₃) values include2.2-2.8 (Ph), 5.92 (CH₃).

PREPARATION 2 2-Methoxyimino-(thien-2-yl)-acetic acids (syn- andantiisomers)

A solution of methoxyamine hydrochloride (5.85 g.) in dry methanol (60ml.) was neutralised (phenolphthalein) with a solution of sodiummethoxide in methanol [from sodium (2.5 g.) and dry methanol (50 ml.)].The precipitated sodium chloride was removed by filtration, and thefiltrate was added to a solution of thien-2-ylglyoxylic acid (10 g.) indry methanol (60 ml.). The resulting solution was refluxed for 1 hour,cooled, and evaporated to an oil. Ether (100 ml.) was added, the mixturewas filtered, and the filtrate was evaporated to an oil (13.06 g.).

The oil (12.5 g.) was dissolved in ether (50 ml.) and an etherealsolution of diazomethane was added until a permanent yellow colourremained. The excess diazomethane was destroyed by leaving the solutionin sunlight for 1 hour. Evaporation of this solution produced an oil(13.2 g.).

The oil (10.33 g.) was purified by preparative plate chromatography(Kieselgel PF₂₅₄ + 366) developing three times with 75% petroleum spirit(b.p. 60°-80°) in benzene, producing a) methyl2-methoxyimino-2-(thien-2-yl)-acetate (syn isomer) (3.44 g., 27%),λ_(max).^(EtOH) 290 nm (ε 11,250), λ_(inf). 271 nm (ε 5,400) ν_(max).(CHBr₃) 1738 and 1230 cm⁻¹ (CO₂ Me). τ values (CDCl₃) include 6.06 (s,CO₂ CH₃), 5.78 (s, OCH₃). b) methyl2-methoxyimino-2-(thien-2-yl)-acetate (anti-isomer) (1.21 g., 9.5%),λ_(max).^(EtOH) 221 and 288 nm (ε 5,020 and 11,000). ν_(max). (CHBr₃)1732 and 1212 cm⁻¹ (CO₂ Me), τ (CDCl₃) values include 6.06 (s, CO₂ Me),6.00 (s, OCH₃) and further fractions which were isomeric mixtures.

2N-Sodium hydroxide (8.27 ml.) was added to a solution of methyl2-methoxyimino-2-(thien-2-yl)-acetate (syn-isomer) (3.28 g.) in methanol(50 ml.) and the solution was stirred at room temperature for 18 hours.Water (20 ml.) was added and the solution was evaporated to removemethanol, and then washed with ethyl acetate. The pH of the solutionunder ethyl acetate (50 ml.) was altered to 2 with 2N-hydrochloric acid.The layers were separated and the aqueous phase was extracted with ethylacetate. The organic extracts were combined, dried, and evaporated to awhite solid (2.58 g.). This was crystallised from cyclohexane, producingthe title compound (syn-isomer) (2.23 g., 73%), m.p.105.5°,λ_(max).^(EtOH) 289 nm (ε 10,100), λ_(inf). 262 and 271 nm. (ε7,750 and 8,150), τ (CDCl₃) values include 0.32 (OH) and 5.92 (OCH₃).Similar hydrolysis of the anti-methyl ester gave2-methoxyimino-(thien-2-yl)-acetic acid (anti-isomer) (0.85 g.),λ_(max).^(EtOH) 286-287 nm (ε 10,200), τ (CDCl₃) values include 1.31(OH) and 5.73 (OCH₃).

PREPARATION 3 syn-t-Butoxyiminothien-2-ylacetic acid

A solution of thien-2-ylglyoxylic acid (6.2g.) and sodium bicarbonate(3.36g.) in water (100 ml.) was added dropwise to a stirred solution oft-butoxyamine hydrochloride (5.65 g.) and sodium bicarbonate (3.78g.) inwater (100 ml.) at 0°-5° and the mixture was stirred at room temperaturefor 18 hr. The mixture was acidified with 2N hydrochloric acid to pH 2.0and extracted with ethyl acetate. The combined extracts were washed withwater, dried and concentrated to give a solid (9.75 g.).Recrystallisation from petroleum (b.p. 60°-80°) gave the title compound(4.0 g., 44%), m.p. 106°-107°, λ_(max). (EtOH)290 nm (ε 11,600), τ(CDCl₃) values include 2.46, 2.66, 2.98 (d doublets, thienyl protons),8.60 (C(CH₃)₃).

PREPARATION 4 2-Ethoxyiminophenylacetic acids (syn and anti-isomers)

Ethoxamine hydrochloride (4.0 g.) and phenylglyoxylic acid (6.0 g.) weredissolved in water (50 ml.), and the resulting solution was basified topH 4.5, and stirred at this pH for 15 hr. Acidification and extractionof the mixture gave, after evaporation of the ethyl acetate, a mixtureof syn and anti ethoxyiminophenylacetic acids (7.4 g., 94%). Fourrecrystallisations from cyclohexane failed to give the pure syn acid.However, evaporation of the mother-liquors from the firstcrystallisation, and recrystallisation of the residue from cyclohexanegave anti-ethoxyiminophenylacetic acid (1.36 g., 17%), m.p. 90.9°-91.6°,λ_(max). (ethanol) 249 nm (ε 7,600), τ (DMSO-d₆) values include 2.52 (s,Ph) 5.74 (q, CH₂), 8.76 (t, --CH₃).

A solution of the mixed acids (4.0 g.) in ether (100 ml.) was treatedwith an ethereal solution of diazomethane until a yellow colourpersisted. Acetic acid was added to destroy excess diazomethane and theether solution was washed with sodium bicarbonate solution, water, andbrine, then dried. Evaporation of the ether gave the methyl esters (4.1g.) as an orange oil. These were separated on five 40 × 20 cm.preparative plates, eluting with petroleum spirit (b.p. 40°-60°)/ether(3:1). The slower band was eluted with chloroform, and removal of thesolvent gave anti-methyl 2-ethoxyiminophenylacetate (1.45 g.) as apale-yellow oil; τ (CDCl₃) values include 2.58 (Ph), 5.66 (q, CH₂), 6.12(s, OCH₃), 8.72 (t, CH₃). Similar treatment of the faster band gavesyn-methyl 2-ethoxyiminophenylacetate (2.45 g.) as a pale yellow oil, τ(CDCl₃) values include 2.3-2.7 (m, Ph) 5.72 (q, CH₂), 6.06 (s, OCH₃ ),8.67 (t, CH₃).

The above syn-methyl ester (2.39 g.) in methanol (60 ml.) was treatedwith sodium hydroxide solution (2N; 12 ml.), and the solution wasstirred for 18 hr. The methanol was removed, and the aqueous mixture,after being acidified to pH 1.5, was extracted with ethyl acetate. Thewashed and dried extracts were evaporated to dryness, and the residuewas recrystallised from cyclohexane to give syn-ethoxyiminophenylaceticacid (836 mg.), m.p. 77.9°-79.0°, λ_(max). (ethanol) 256.5 nm (ε12,800); τ (DMSO-d₆) values include 2.48 (m, Ph), 5.74 (q, CH₂), 8.71(t, CH₃).

PREPARATIONS 5-23 2-Alkoxyiminoarylacetic Acids

General Procedures

A mixture of the substituted glyoxylic acid and an excess (10 to 15%) ofthe alkoxyamine hydrochloride was suspended in water or aqueous ethanol,stirred, and the pH of the mixture adjusted to between 4 and 5 (MethodB) with sodium hydroxide solution (N to 10N). A clear solution at pH 4to 5 was maintained during the reaction by further additions of sodiumhydroxide solution and ethanol as needed. The reaction mixture was keptat room temperature until all of the ketoacid was consumed (it may benecessary to add a further portion of the more volatile alkoxyamines).The progress of the reaction was followed by acidification of analiquot, extraction with ethyl acetate and thin layer chromatography ofthe extract on silica plates (developed with a mixture of chloroform;methanol: acetic acid; 18:2:1). The alkoxyiminoacetic acids were lesspolar than the starting keto-acids. The reaction times were 2 hr. to 2days. Reactions carried out at pH 7-8 are designated Method A. Whenreaction was complete the pH of the mixture was adjusted to between 7and 8 and the ethanol (if any) was removed by evaporation. The aqueousmixture was extracted with ether, the extract discarded and the aqueousphase acidified to pH < 2 with dilute hydrochloric acid. The mixture wasextracted with ethyl acetate, the extract dried and evaporated to givethe crude product which was purified by one of the following methods:

(a) Crystallisation and recrystallisation (if needed) from a suitablesolvent,

(b) The crude product dissolved in ether was treated with a small excessof a solution of diazomethane in ether. The excess reagent was destroyedwith acetic acid and the solution washed with sodium bicarbonatesolution and evaporated to give the crude methyl esters. The esters wereseparated by preparative thick layer chromatography or columnchromatography on silica, and then hydrolysed conventionally with alkalito give the pure syn acid,

(c) The mixture of methyl esters was prepared as in (b) and the isomersseparated by crystallisation from a suitable solvent and similarlyhydrolysed.

These methods were employed to prepare the intermediates listed in Table1 (syn-isomers)

                                      TABLE 1                                     __________________________________________________________________________     ##STR39##                                                                                                                               Yield              Prep-                                                      %                  ara-                      Puri-                   λ.sub.max.                                                                      (before            tion                  Meth-                                                                             fica-    τ values                                                                          (solvent)                                                                            nm       purifi-            No. R         R.sup.a od  tion                                                                              Mp. °                                                                       R       R.sup.a                                                                              (EtOH)                                                                              ε                                                                        cation             __________________________________________________________________________    5   Ph        C(CH.sub.3).sub.3                                                                     A   (a) 127-129°                                                                    2.2-2.7 8.62   257   13,060                                                                           100                                                   (DMSO-d.sub.6)                             6   Ph        CH.sub.2 Ph                                                                           A   (a) 103.3°                                                                      2.2-2.7 4.67 (CH.sub.2)                                                                      257   15,150                                                                           100                                                   (CDCl.sub.3)                               7   Ph                                                                                       ##STR40##                                                                            B   (a) 110-111°                                                                    2.44 (DMSO-d.sub.6)                                                                   4.58 (CH.sub.2) 2.92,2.78,2.44                                                thien-2-yl).                                                                          --    --                                                                              --                      ##STR41##                                                                              CH.sub.3                                                                              B   (a) 108-109°                                                                    2.61-2.91 (CDCl.sub.3)                                                                5.92   289   10,700                                                                           91                 9                                                                                  ##STR42##                                                                              C.sub.2 H.sub.5                                                                       B   (a) 89.5-91.5°                                                                  2.29,2.76,2.86 (DMSO-d.sub.6)                                                         5.79 (CH.sub.2) 8.72                                                          (CH.sub.3)                                                                           289.5 12,500                                                                           87                 10                                                                                 ##STR43##                                                                              CH.sub.2 Ph                                                                           B   (a) 114-115°                                                                    2.29,2.73,2.84                                                                        2.59 (Ph) 4.77                                                                       290.sub.2)                                                                          12,300                                                                           88                 11                                                                                 ##STR44##                                                                              CH.sub.2 CH.sub.2 Br                                                                  B   (b) 92.6°                                                                       2.23;2.71;2.83                                                                        5.54;6.28                                                                            289   12,200                                                                           77                 12                                                                                 ##STR45##                                                                              CH.sub.3                                                                              B   (b) 98-99°                                                                      1.38 1.8-2.1 2.1-2.5                                                                  5.9    294.5  8,100                                                                           96                 13                                                                                 ##STR46##                                                                              C(CH.sub.3).sub.3                                                                     A   (b) 122-123°                                                                    1.3-1.5 1.3-2.1 2.2-2.5                                                               8.62   296.5  9,300                                                                           96                 14                                                                                 ##STR47##                                                                              CH.sub.2 Ph                                                                           A   (a)  --  1.53,1.92,2.2-2.7                                                                     2.50 (Ph) 4.64                                                                       294.sub.2)                                                                           8,300                                                                           86                 15                                                                                 ##STR48##                                                                              CH.sub.3                                                                              B   (a) 85-87°                                                                      2.10,3.18,3.33                                                                        6.06   275   21,500                                                                           81                 16                                                                                 ##STR49##                                                                              C(CH.sub.3).sub.3                                                                     B   (a) 110.5- 111.5°                                                               2.12,3.24,3.35                                                                        8.70   275.5 16,040                                                                           95                 17                                                                                 ##STR50##                                                                              CH.sub.2 Ph                                                                           B   (a) 104-105.5                                                                          2.12,3.19,3.33                                                                        2.58 (Ph) 4.75                                                                       277.sub.2)                                                                          27,650                                                                           81                 18                                                                                 ##STR51##                                                                              CH.sub.3                                                                              B   (c) 129-130°                                                                    1.40,1.83 1.95,2.44                                                                   5.92   233 284 296.5 306.5                                                                 22,900 10,900                                                                 10,500  9,270                                                                    99                 19                                                                                 ##STR52##                                                                              C(CH.sub.3).sub.3                                                                     B   (a) 175-176°                                                                    1.88,2.03,2.3-2.7                                                                     8.6    234 284.5 297 307.5                                                                 21,900 11,200                                                                 10,800 9,400                                                                     93                 20                                                                                 ##STR53##                                                                              CH.sub.3                                                                              B   (a) 143-144° (dec)                                                              2.00,2.36,2.55                                                                        6.00   231 252.5 296.5                                                                     5,400 7,300                                                                   23,600                                                                           98                 21                                                                                 ##STR54##                                                                              CH.sub.2 Ph                                                                           B   (a) 103-1035°                                                                   2.22,2.32,2.65                                                                        2.59 (Ph) 4.76                                                                       259.sub.2)                                                                          15,400                                                                           --                 22                                                                                 ##STR55##                                                                               ##STR56##                                                                            B   (a) 104.8 - 105.4°                                                              2.17;3.25;  3.40                                                                      4.92 (CH.sub.2) 2.33,3.5.                                                     (furyl protons)                                                                      276   16,300                                                                           97                 23                                                                                 ##STR57##                                                                              C.sub.2 H.sub.5                                                                       B   (a) 91-92°                                                                      2.10,3.19, 3.33                                                                       5.79,8.25                                                                            274.5 15,800                                                                           92                 __________________________________________________________________________

PREPARATION 24 2-Methoxyiminopyrid-3'-ylacetic acid (syn- andantiisomers)

Pyrid-3-ylglyoxylic acid (3.02 g.) and methoxylamine hydrochloride (2.59g) were heated under reflux in ethanol (50 ml.) and treated with asolution of sodium ethoxide in ethanol until the mixture was justalkaline to phenophthalein. The mixture was maintained under reflux for11/2 hours. Further portions of methoxylamine hydrochloride (0.5 g) andethanolic sodium ethoxide were added and refluxing continued for afurther 1 hour. The resulting mixture was filtered through Kieselguhrand evaporated to dryness. The residue was dissolved in a small volumeof ethanol and the remaining fine suspension was removed by filtrationthrough Kieselguhr. Dilution of the filtrate with ethyl acetate gave acrystalline solid. The solid was washed well with ethyl acetate anddried to yield 2-methoxyiminopyrid-3'-ylacetic acid as an isomericmixture (2.72 g., 76%), λ_(max). (pH 6 buffer) 250 nm (ε 6,630),ν_(max). (Nujol) 1610 (CO₂ ⁻) and 1038 cm.⁻¹ (═C-O--), τ (d₆ DMSO) 1.21,1.43, 2.02, 2.60 (multiplets; aromatic protons), 6.20 (s; OCH₃).

PREPARATION 25 (a) Methyl2-(1 -ethoxy)ethoxyimino-2-(thien-2-yl)acetate(syn-isomer)

To a stirred mixture of methyl 2-hydroxyimino-2-(thien-2-yl)acetatesyn-isomer (3.98 g.) and ethyl vinyl ether (2.5 mls) in ethyl acetate(25 mls) was added phosphorous oxychloride (2 drops). After 20 mins. at50° the ethyl acetate was washed with saturated sodium bicarbonatesolution, dried over sodium sulphate and evaporated to an oil, givingmethyl 2-(1 -ethoxy) ethoxyimino-2-(thien-2-yl)acetate (syn-isomer) (5.7g; 100%) λ_(max). (EtOH) 289 nm (ε 11,700), τ (CDCl₃ ; 60 MHz) 2.61(multiplet; thienyl H₅), 2.82 to 2.97 (multiplet; thienyl H₃ and H₄),4.64 (quartet, J 5 Hz; ##STR58## 6.06 (singlet, --COOCH₃), 6.24(quartet, J 7 Hz, OCH₂), 8.56 (doublet J 5 Hz; CH-CH₃), 8.79 (triplet, J7 Hz; O.CH₂ CH₃).

(b) 2-(1-Ethoxy)ethoxyimino-2-(thien-2-yl)acetic acid sodium salt(syn-isomer)

1N-Sodium hydroxide (1 equiv.) and enough methanol to form a homogeneoussystem were added to methyl 2-(1-ethoxy)ethoxyimino-2-(thien-2-yl)acetate (syn-isomer) (5.7 g.). After 4hrs. at 50° the methanol was evaporated and the residue azeotroped withbenzene/methanol giving a white solid, 2-(1-ethoxy)ethoxyimino-2-(thien-2-yl)acetic acid sodium salt syn-isomer)(4.6 g, 78.5%), λ_(max). (pH 6 buffer) 287.5 nm (ε 10,650), τ (D₂ O)values include 2.42 (multiplet; thienyl H₅), 2.68 to 2.84 (multiplet;thienyl H₃ and H₄), 4.63 (quartet, J 5 Hz; ##STR59## 6.21 (quartet, J 7Hz; --CH₂ -CH₃), 8.57 (doublet, J 5 Hz; ##STR60## 8.82 (triplet, J 7 Hz;-CH₂ -CH₃).

PREPARATION 26 syn-Then-2-yloxyimino(thien-2-yl)acetic acid

Then-2-yloxamine hydrochloride (7.37 g.) and thien-2-ylglyoxylic acid(6.24 g.) were dissolved in ethanol (110 ml.) and water (20 ml.). The pHof the solution was adjusted to 5.0, and this solution was stirred for22 hr. The ethanol was evaporated off, and the aqueous mixture wasneutralised, washed twice with ether, then acidified to pH 1.5. The acidmixture was extracted with ethyl acetate. The combined extracts werewashed, dried and evaporated to dryness to give a yellow oil (9.2 g.,86%) which crystallised on standing. TLC indicated the solid to be amixture of isomers. Recrystallisation of this solid several times fromcyclohexane effected no separation of isomers. The mixture of acids (5.0g.) was esterified with diazomethane to give the mixture of methylesters, as a pale-yellow oil.

To a solution of the mixture of methyl esters (2.14 g.) in methanol (50ml.) was added 2N sodium hydroxide solution (7.6 ml.). After stirringthis solution for 0.5 hr., the solution was neutralised. The methanolwas evaporated and the aqueous residue was extracted with ethyl acetate.The extracts were washed, dried, and evaporated to dryness to give ayellow oil (1.0 g.). This oil was dissolved in methanol (25 ml.) andstirred for 18 hr. with 2N sodium hydroxide solution (5 ml.). Methanolwas removed by evaporation and the aqueous residue, after washing withethyl acetate then acidification to pH 1.7, was extracted with ethylacetate. The extracts were washed, dried, and evaporated to dryness togive a solid (730 mg.). Recrystallisation of this solid twice fromcyclohexane gave syn-then-2-yloxyimino(thien-2-yl)acetic acid (369 mg.),m.p. 101°-102°, λ_(max). (EtOH) 239, 289.5 nm (ε 11,700, 12,300), τ(DMSO-d₆) values include 4.67 (s, CH₂).

PREPARATION 27 syn-2-Benzyloxyiminobenzo[b]-thien-3'-ylacetic acid

Benzo[b]-thien-3-ylglyoxylic acid (2.27 g) and benzyloxyaminehydrochloride (1.915 g) were dissolved in ethanol (70 ml) and water (30ml). The solution was adjusted to pH 4.5 with 40% w/v sodium hydroxidesolution and stirred at this pH for 2 hr. The solution was stoodovernight and adjusted to pH 9 then washed with ether. The aqueous phasewas acidified under ethyl acetate and the organic layer was washed withwater, saturated brine and dried. Evaporation gave a mixture of syn andanti-isomers as a buff crystalline solid (3.4 g., 99%). The crude acidin ether was treated with excess diazomethane in ether at 0°-5°. Theexcess reagent was destroyed with acetic acid and the ether solution waswashed with sodium bicarbonate, water and dried. Evaporation gave a palebrown oil (3.34 g., 93%). The crude product in methanol (100 ml.) wastreated with sodium hydroxide solution (1N, 10 ml) at room temperaturefor 1 hr. The hydrolysis was followed by thin layer chromatography onsilica. Hydrochloric acid (2N 5 ml.) was added to stop the hydrolysisand methanol was removed by evaporation. Ethyl acetate was added and theanti-2-benzyloxyimino benzo[b]-thien-3'-ylacetic acid was removed bywashing with sodium bicarbonate. The ethyl acetate layer was washed withwater and dried and evaporated to a pale orange oil (1.99 g., 56%). Thiswas treated in methanol (90 ml.) with sodium hydroxide (1N; 10 ml) atroom temperature for 7 hr. A further aliquot of sodium hydroxide (1N; 5ml) was added and the solution stood for 2 days to complete hydrolysis.The methanol was removed by evaporation and the residue dissolved inethyl acetate and water. The mixture was adjusted to pH 1.5 and theethyl acetate layer was washed with water, saturated brine and dried.Evaporation gave yellow crystals (1.82 g, 50%) Crystallization from amixture of benzene and cyclohexane gave the title compound as paleorange crystals (1.29 g., 36%), m.p. 120.5°-121°, λ_(max). (EtOH) 232,285.5, 296.5 306.5 nm. (ε 22,500, 11,800, 11,500, 10,400), τ values(DMSO-d₆) include 1.90, 1.97, 2.3-2.7 (aromatic protons), 4.64 (CH₂singlet).

PREPARATION 28 syn-2-Benzyloxyiminobenzo-[b]-thien-2'-ylacetic acid

Benzo[b]-thien-2-ylglyoxylic acid (3.092 g) and benzyloxyaminehydrochloride (2.72 g.) in ethanol (170 ml.) and water (70 ml.) wereadjusted to pH 4.5 with sodium hydroxide (40%). The solution was stirredat this pH at room temperature for 6 hr. Benzyloxyamine hydrochloride(500 mg.,) was added and the solution stood at room temperatureovernight. The solution was adjusted to pH 8 and washed with ether. Theaqueous phase was acidified under ether to pH 1.5. The ether layer waswashed with water and dried. Evaporation gave a cream coloured solid(4.28 g, 91%) as an isomeric mixture.

The crude isomeric mixture was treated in ether with excess diazomethanein ether at 0°-5°. The excess reagent was destroyed with acetic acid andthe ether solution was washed with sodium bicarbonate, water and dried.Evaporation gave an oil (4.45 g., 91%). This was dissolved in methanol(140 ml.) and treated at room temperature with sodium hydroxide solution(1N; 14 ml.) for 21/4 hr. Hydrochloric acid (2N, 7 ml.) was added andthe alcohol was removed by evaporation. The aqueous phase waspartitioned between sodium bicarbonate solution and ether. The etherlayer was washed with water and dried. Evaporation gave an oil (2.16 g.,44%). This was hydrolysed directly in refluxing methanol (70 ml.) withsodium hydroxide (1N; 7 ml) for 4 hr. The methanol was removed byevaporation and the residue partitioned between water and a littleether. The aqueous layer was acidified under ether to pH 1.5 and theether layer was washed with water, dried and evaporated to give a palecream solid (1.97 g, 42%). Crystallisation from a mixture of benzene andcyclohexane gave the title compound as a white crystalline solid, (1.61g; 35%), m.p. 141°-143° (dec.), λ_(max). (EtOH) 230.5, 253, 297.5 nm (ε16,400; 7,400; 24,100), τ (DMSO-d₆) values include 2.00, 2.36, 2.55(aromatic protons), 4.71 (CH₂ singlet).

PREPARATION 29 (a) (2-t-Butoxycarboxamido)ethoxyimino-thien-2-ylaceticacid (syn-isomer)

N-Carbo-t-butoxy-2-bromoethylamine (1.12 g.) was added to a solution ofthe sodium salt of methyl syn-hydroxyimino-thien-2-ylacetate (1.035 g.)in benzene: dimethylformamide (2:1 v/v, 30 ml.), and the mixture wasstirred for 16 hr. Ethyl acetate (50 ml.) was added, and the mixture waswashed several times with water, dried, and evaporated to dryness togive methyl syn-(2-t-butoxycarboxamidoethoxy)imino-thien-2-ylacetate(1.21 g, 75%), τ (CDCl₃) values include 2.62, 2.86, 2.99 (thienylprotons), 5.10 (NH), 6.06 (s, CH₃), 8.58 (s,C(CH₃)₃).

The crude ester (1.1 g) in methanol (20 ml) was treated with 2N sodiumhydroxide solution (3.4 ml.), and stood 16 hr. The methanol wasevaporated off, and the aqueous residue, after washing with ether, wasacidified to pH 2.0, and extracted with ethyl acetate. The extracts werewashed (water, saturated brine), dried, and evaporated to dryness.Recrystallisation of the residue from cyclohexane gave the titlecompound (951 mg., 90%), m.p. 112.8°-114.4° λ_(max). (EtOH) 290.5 nm. (ε11,600), τ (DMSO-d₆) values include 2.19, 2.6-2.9 (thienyl protons),3.14 (NH), 8.52 (s, C(CH₃)₃).

The alkylating agent used for the above preparation was made as follows:

(b) N-Carbo-t-butoxy-2-bromoethylamine

A mixture of t-butyl azidoformate (15.81 g) and triethylamine (30 ml)was added dropwise to a stirred suspension of 2-bromoethylaminehydrobromide (20.5 g.), in methylene chloride (100 ml.). The mixture wasstirred for 3 hr., then filtered. The filtrate was concentrated to asmall volume, and the residue was distributed between ether and water.The ether layer was dried, then distilled under reduced pressure,collecting the fraction b.p. 92°-94°/0.9 nm asN-carbo-t-butoxy-2-bromoethylamine (1.756 g.)

PREPARATION 30 Pyrid-2-ylmethoxyimino(thien-2-yl)acetic acid(syn-isomer)

2-Chloromethylpyridine (a 25% solution in toluene, 2.8 ml.) was added toa solution of the sodium salt of methylsyn-hydroxyimino-thien-2-ylacetate (1.035 g.) inbenzene:dimethylformamide (30 ml, 2:1, v/v). The solution was stirredfor 18 hr., ethyl acetate (50 ml.) was added, and the mixture was washedseveral times with water, dried and evaporated to dryness to give adark-green oil (1.4 g.). This oil was chromatographed on two 40 × 20 cm.preparative chromatography plates, eluting with chloroform. The singlemajor band was eluted off the silica with chloroform: ethanol (9:1 v/v)to give after evaporation of the solvent, methylpyrid-2-ylmethoxyimino(thien-2-yl)acetate (889 mg., 47%) (75% syn, 25%anti-isomer). A solution of the crude ester (828 mg.) in methanol (20ml) and 2N sodium hydroxide solution (3 ml.) was stood 16 hrs. Afterremoval of the methanol, the aqueous mixture was acidified to pH 2.0 inthe presence of methylene chloride. The acid mixture was extracted withmethylene chloride and the extracts were washed (water, brine), dried,and evaporated to dryness. Trituration of the residue with ether gavethe title compound (210 mg, 27%), m.p. 152.1°-152.9°, λ_(max). (EtOH)260.5, 266, 289 nm (ε 12,300; 12,000; 11,700), τ (DMSO-d₆) valuesinclude 4.66 (singlet, CH₂).

PREPARATION 31 n-Butoxyimino-thien-2-ylacetic acid (syn-isomer)

1-Bromobutane (0.6 ml.) was added to a solution of methylsyn-hydroxyimino-thien-2-ylacetate sodium salt (prepared by treatingmethyl syn-hydroxyiminothien-2-ylacetate with 1 equivalent sodiummethoxide) (1.0 g.) in benzene:dimethylformamide (2:1, 15 ml.) and themixture was stirred for 17 hours at room temperature then poured intowater. The aqueous solution was extracted with ethyl acetate, washedwith water, dried and evaporated to give syn methyl ester (0.88 g) as apale yellow oil.

2N-Sodium hydroxide (4.0 ml.) was added to a solution of the syn methylester (0.85 g.), in methanol (10 ml.) and the mixture was left at roomtemperature for 18 hr. The methanol was removed by evaporation; theaqueous residue was diluted with water, washed with ether and acidifiedto pH 2.0 with 2N-hydrochloric acid. The mixture was extracted withethyl acetate; the combined extracts were washed with water, dried andevaporated to give the title compound (0.74 g., 81%) as a pale yellowoil, τ values (DMSO-d₆) include 2.30 2.7-3.0 (thien-2-yl protons), 5.84(OCH₂), 9.10 (CH₃).

PREPARATION 32 2-Methoxymethoxyimino-(thien-2-yl)acetic acid(syn-isomer)

A solution of sodium methoxide in methanol (approx. 0.2 M) was added tomethyl 2-hydroxyimino-2-(thien-2-yl) acetate (syn-isomer) (0.5 g) andthe solution formed was evaporated to a yellow oil which on azeotropingwith petrol (b.p. 40°-60°) gave the sodium salt of methyl2-hydroxyimino-2-(thien-2-yl) acetate (syn-isomer) (0.49 g., 88%). To astirred solution of the sodium salt (0.49 g.) in benzene/DMF (5 mls.,2:1). was added chlorodimethyl ether (0.22 mls). After 10 mins. thereaction was poured into saturated sodium bicarbonate solution andextracted with benzene. The combined extracts were washed with water,dried over sodium sulphate and evaporated to a yellow oil, methyl2-methoxymethoxyimino-(thien-2-yl) acetate (syn-isomer) (0.62 g; 100%),λ_(max). (EtOH) 288 nm (ε 10,300), ν_(max). (CHBr₃) 1730 (COOCH₃), 1660cm.⁻¹ (--C═N--), τ (CDCl₃) values include 2.61-2.83 (multiplet,thien-2-yl), 4.83 (singlet, CH₂), 6.06 (CO₂ CH₃) 6.56 (singlet, CH₂OCH₃).

A solution of sodium hydroxide (4 ml, 2N) and methanol were added to themethyl ester (0.4 g.). After 30 mins. the reaction was poured into waterand washed with ethyl acetate. The aqueous layer was acidified to pH 1using 2N-hydrochloric acid and extracted with ethyl acetate. The ethylacetate was dried and evaporated to a colourless oil which wasazeotroped with petrol (bp. 40°-60°) to yield a white solid, syn2-methoxymethoxyimino-(thien-2-yl)acetic acid (0.21 g; 55%), m.p. 61.2°,λ_(max). (EtOH) 286 nm (ε 10,400), ν_(max). (Nujol) 1732, 2600 cm.⁻¹(CO₂ H), τ (DMSO-d₆) 2.26 (multiplet; thienyl H₅), 2.7-2.9 (multiplet,thienyl H₃ and H₄), 4.88 (singlet, O-CH₂ --), 6.6 (singlet, OCH₃).

PREPARATION 33 2-t-Butoxyiminobenzo[b]-thien-2'-ylacetic acid(syn-isomer)

Benzo[b]-thien-2-ylglyoxylic acid (3.09 g) andt-butoxyaminohydrochloride (1.98 g) were dissolved in 50% aqueousethanol (100 ml). The solution was adjusted to pH 4.5 with sodiumhydroxide solution and maintained at such for 4 hr. at room temperature.Thin-layer chromatography showed incomplete reaction.t-Butoxyaminohydrochloride (500 mg.) was added and the solution kept atroom temperature overnight. The alcohol was removed by evaporation andthe aqueous phase adjusted to pH 8 and washed with ether. The aqueousphase was then acidified to pH 1.5 under ether. The ether solution waswashed with water and dried. Evaporation gave a cream solid (4.05 g.).Fractional crystallisation from cyclohexane gave the anti-isomer of thetitle compound (1.6 g.). The mother liquors were combined and evaporatedto give a cream solid (2.11 g.) that was treated in ether with excessdiazomethane in ether at 0°-5°. The excess reagent was destroyed byacetic acid and the ether solution washed with sodium bicarbonate, waterand dried. Evaporation gave an oil (1.75 g.). This was dissolved inmethanol (70 ml) and treated with sodium hydroxide solution (N: 7 ml.)at room temperature for 3 hr. Hydrochloric acid (2N: 3.5 ml) was addedand the methanol was removed by evaporation. The aqueous residue waspartitioned between ether and sodium bicarbonate solution. The etherlayer was washed with water and dried. Evaporation gave an oil (0.92 g.)that was dissolved in methanol (20 ml.) and treated with sodiumhydroxide (N: 7 ml) at reflux temperature for 3hr. Sodium hydroxide (N:5ml) was added and the solution refluxed for 6 hr. The methanol wasremoved by evaporation and the residue partitioned between ether andwater. The aqueous phase was acidified (pH 1.5) under ether and theether layer washed with water, dried and evaporated to give a paleorange crystalline solid (760 mg. 18%). Crystallisation from benzenecontaining cyclohexane gave syn-t-butoxyiminobenzo[b]-thien-2 -ylaceticacid (430 mg.) m.p. 108°-9°, λ_(max). (EtOH) 231, 253, 297 nm (ε 17,000,7,240, 24,500).

PREPARATION 34 Benzo[b]-thien-2-ylglyoxylic acid andBenzo[b]-thien-3-ylglyoxylic acid

A mixture of 2- and 3-acetylbenzo[b]-thiophene (ca. 1:1) (11.0 g.) inpyridine (80 ml.) was warmed to 60° with vigorous stirring and seleniumdioxide (9.92 g.) was added portionwise. The mixture was heated to 110°C and an exothermic reaction occurred, the temperature rising to 120°.The reaction was stirred at 90° for 45 mins. and then left to cool.Water (80 ml.) was added and the mixture filtered through a kieselguhrpad. The pyridine was removed by evaporation and the aqueous residueagain filtered. The filtrate was acidified to pH 2 under ether with 40%orthophosphoric acid (40 ml).

The aqueous phase was extracted with ether and the ether fractions werecombined, washed with water and dried. Evaporation gave an orangecrystalline solid (11.0g., 86%). Crystallisation from benzene (100 ml)gave bright yellow crystals of benzo[b]thien-2-ylglyoxylic acid (2.3 g.18%), m.p. 175.9°, λ_(max). (EtOH), 233, 247, λinfl. 308 nm. (ε 11,400;7,200; 14,600), τ (DMSO-d₆) values include 1.83 (C-4 and C-7 protons),1.42 (C-3 proton), 2.40 (C-5 and C-6 protons). The mother liquor wasconcentrated to an orange oil which crystallised on standing (8 g.).Recrystallisation from benzene (20 ml.) gave pale yellow needles ofbenzo-[b]-thien-3-ylglyoxylic acid (1.6 g., 12.5%), m.p. 92°-93°,τ(DMSO-d₆) values include 0.83 (C-2 proton), 1.32 (C-4 proton), 1.79 (C-7proton), 2.40 (C-5 and C-6 protons), λ_(max). (EtOH) 235; 310.5 nm (ε11,200 and 7,400).

2-ALKOXYIMINOARYLACETYL CHLORIDES Preparation 35

syn-2-Methoxyiminophenylacetyl chloride

Phosphorous pentachloride (5.21 g) was added in portions to a stirredsuspension of syn-2-methoxyiminophenylacetic acid (4.51 g.) in drybenzene (20 ml.). Thionyl chloride (0.3 ml) was added to the solution,which was refluxed for 30 minutes. Benzene was removed by evaporation,and the residue distilled, producing a mixture of syn- and anti- acidchlorides (ca. 1:1) as a colourless oil (3.08 g., 62%), b.p. 74° (0.01mm). A repeat of this reaction (on 5.04 mmole) at room temperature alsoproduced a mixture of the isomeric acid chlorides.

The acid chlorides were separated and purified by preparative platechromatography, developing three times with petroleum spirit (b.p.60°-80°) producing the title compound as a colourless oil (1.43 g. 24%).

In a further experiment a mixture of syn- and anti-2-methoxyiminophenylacetic acids (10 g., ca 1:1) were converted to amixture of acid chlorides as above and chromatographed on silica gel(120 g., Hopkins and Williams, MFC) using petroleum spirit (b.p.60°-80°) to give syn-2-methoxyiminophenylacetyl chloride (4.32 g., 39%).

General Method for Converting a 2-Alkoxyiminoarylacetic Acid into itsAcid Chloride without Isomerisation

A solution of the pure syn- or 2-alkoxyiminoarylacetic acid (1 equiv.)in methanol (ca. 2-4 ml./mmole.) was treated with sodium methoxide (1equiv.) in methanol at 0°-25° and the mixture evaporated to give thesodium salt which may be dried by azeotroping with several portions ofbenzene and/or drying in vacuo over phosphorus pentoxide.

The anhydrous sodium salt (1 equiv.) is suspended in dry benzene (ca. 5ml/mmole) containing a few drops of dry dimethylformamide and treatedwith freshly distilled oxalyl chloride (1-2.5 equiv.). The mixture isstirred at room temperature for 1 hr. and then evaporated to removebenzene. The resulting acid chlorides were not characterised but weredissolved in acetone or methylene chloride and used immediately toacylate the appropriate cephalosporin nucleus.

The following acids were converted into their acid chlorides in thisway:

Syn-2-Ethoxyiminophenylacetic acid,

Syn-2-t-Butoxyiminophenylacetic acid,

Syn-2-Benzyloxyiminophenylacetic acid,

Syn-2-Then-2'-yloxyiminophenylacetic acid,

Syn-2-Methoxyimino-(thien-2-yl)acetic acid,

Syn-2-Ethoxyimino-(thien-2-yl)acetic acid,

Syn-2-Benzyloxyimino-(fur-2-yl)acetic acid.

Syn-2-n-Butoxyimino-(thien-2-yl)-acetic acid,

Syn-2-t-Butoxyimino-(thien-2-yl)-acetic acid,

Syn-2-(2-Bromoethoxy)imino-(thien-2-yl)-acetic acid,

Syn-2-(2-t-Butoxycarbonylaminoethoxy)imino-(thien-2-yl)acetic acid,

Syn-2-Benzyloxyimino-(thien-2-yl)acetic acid,

Syn-2-Then-2'-yloxyimino-(thien-2-yl)-acetic acid,

Syn-2-(1-Ethoxy)ethoxyimino-(thien-2-yl)-acetic acid,

Syn-2-(Pyrid-2-ylmethyl)-oxyimino-(thien-2-yl)acetic acid,

Syn-2-Methoxyiminonaphth-1'-ylacetic acid,

Syn-2-t-Butoxyiminonaphth-1'-ylacetic acid,

Syn-2-Benzyloxyiminonaphth-1'-ylacetic acid,

Syn-2-Methoxyiminobenzo-[b]-thien-3'-ylacetic acid,

Syn-2-t-Butoxyiminobenzo-[b]-thien-3'-ylacetic acid,

Syn-2-Benzyloxyiminobenzo-[b]-thien-3'-ylacetic acid,

Syn-2-Methoxyiminobenzo-[b]-thien-2'-ylacetic acid,

Syn-2-t-Butoxyiminobenzo-[b]-thien-2'-ylacetic acid,

Syn-2-Benzyloxyiminobenzo-[b]-thien-2'-ylacetic acid,

Syn-2-Methoxyimino(fur-2-yl)acetic acid,

Syn-2-t-Butoxyimino-(fur-2-yl)acetic acid,

Syn-2-Benzyloxyimino-(fur-2-yl)-acetic acid,

Syn-2-Furfuryloxyimino-(fur-2-yl)-acetic acid, and

Syn-2-ethoxyimino-(fur-2-yl)-acetic acid.

Preparation A Then-2-yloxamine hydrochloride (used as a startingmaterial in Preparation 7)

(a) N-(Then-2-yloxy)phthalimide

Anhydrous potassium carbonate (11.04 g.) was added to a stirredsuspension of N-hydroxyphthalimide (17.12 g.) in dry dimethyl sulphoxide(200 ml.). A brown colour developed, 2-Chloromethylthiophene (28.5 g.)was added dropwise and the mixture was stirred for 16 hr., during whichtime the colour disappeared. The suspension was poured into water (800ml.) and cooled to 5°. The white precipitate was filtered off, andrecrystallised from ethanol to give colourless needles ofN-(then-2-yloxy)phthalimide (23.4 g., 83%), m.p. 129.7° - 130.9° τvalues (DMSO-d₆) are 4.58 (CH₂), 2.28, 2.68, 2.90 (thienyl protons) 2.08(phthalimide protons)

(b) Then-2-yloxamine hydrochloride

A mixture of N-(then-2-yloxy)phthalimide (22.4 g.) 100% hydrazinehydrate (5 g) and ethanol (600 ml.) was heated under reflux for twohours. Initially, a yellow solution was formed, but soon solid began toprecipitate. The mixture was cooled, then acidified with concentratedhydrochloric acid (12 ml.). The precipitated phthalhydrazide wasfiltered off and washed with ethanol (3 × 50 ml.) and water (100 ml.).The combined filtrate and washings were evaporated to dryness, and theresidue, suspended in water, was basified with 2N sodium hydroxidesolution. The basic mixture was extracted with ether, and the combinedextracts were washed (water, saturated brine), dried, and saturated withdry hydrogen chloride. The precipitated solid was collected and wellwashed with ether to give then-2-yloxamine hydrochloride, (12.45 g.,87%), m.p. 157.1° - 157.5°. A sample recrystallised from ethanol/etherhad m.p. 161.7 - 162.1 τ values (DMSO-d₆) include 4.69 (CH₂), 2.30,2.72, 2.90 (thienyl protons)

Preparation B Furfuryloxamine Hydrochloride (used as a starting materialin Preparation 22)

(a) N-Furfuryloxyphthalimide

To a stirred mixture of N-hydroxyphthalimide (41 g.), anhydrouspotassium carbonate (26.4 g.) and dry dimethyl sulphoxide (400 ml.) wasadded 2-chloromethylfuran (freshly prepared, but undistilled, from 46.2furfuryl alcohol according to the method of W. R. Kirner JACS, 1928, 50,1955). The mixture was stirred for 18 hr., then poured in water (1.5 l).The precipitated solid was filtered off, washed well with water, andrecrystallised from ethanol to give N-furfuryloxyphthalimide (42.8 g.,70%), m.p. 145.3°-146.2° τ values (DMSO-d₆) are 4.80 (CH₂), 2.22, 3.30,3.50 (furyl protons) 2.08 (phthalimide protons).

(b) Furfuryloxamine Hydrochloride

100% Hydrazine hydrate (20 ml.) was added to a stirred solution ofN-furfuryloxyphthalimide (42.0 g.) in methylene chloride (600 ml.). Acopious precipitate formed immediately, and the mixture was stirred for45 min. 5N Ammonium hydroxide solution (500 ml.) was added to dissolvethe precipitate, the two layers were separated, and the aqueous layerwas washed twice with methylene chloride. The combined methylenechloride extracts were washed (saturated brine) and dried. Methylenechloride was evaporated off, and the residual liquid was dissolved inether (250 ml.). Dry hydrogen chloride was passed into this solution forone hour. The precipitated solid was filtered off, washed with ether,dried, and recrystallised from isopropanol to give furfuryloxaminehydrochloride (12.89 g., 50%), m.p. 135°-136° (decomp)τ values (DMSO-d₆)include 4.87 (CH₂), 2.20, 3.27, 3.44 (furyl protons).

PREPARATION C

The general procedures described in Preparations 5-23 for thepreparation of 2-alkoxyiminoarylacetic acids were employed to preparethe intermediates listed in tabular form below (the Table may beregarded as a continuation of Table 1).

    __________________________________________________________________________     ##STR61##                                                                    Prep-                                                                         ara-                      Puri-                   λ.sub.max.           tion                      fica-     τ values (DMSO-d.sub.6)                                                                 nm       Yield              No. R         R.sup.a Method                                                                            tion                                                                              Mp.°                                                                        R        R.sup.a                                                                             (EtOH)                                                                             ε                                                                          %                 __________________________________________________________________________    36  Ph        n-C.sub.4 H.sub.9                                                                     B   (b) oil  2.4- 2.6                                                                              5.82,2.3-2.8,                                                                        257  11,500                                                                            100                                                           9.08                               37  Ph        n-C.sub.3 H.sub.7                                                                     B   (b) oil  2.48    5.88, 8.40,                                                                          257  11,400                                                                            100                                                           9.09                               38                                                                                 ##STR62##                                                                              C.sub.2 H.sub.5                                                                       B   (a) 74.0°                                                                       2.2-2.4, 2.65                                                                         5.81, 8.75                                                                           258.5                                                                              13,800                                                                            96                 39                                                                                 ##STR63##                                                                              C.sub.2 H.sub.5                                                                       B   (a) 125.5 - 126°                                                                2.1-2.8, 2.75                                                                         5.69, 8.71                                                                           228 inf 290 297                                                                     7,200 22,940                                                                 24,600 22,500                                                                     84                 __________________________________________________________________________

2-ALKOXYIMINOARYLACETYL CHLORIDES (CONTINUED)

The following acids were converted into their acid chlorides using thegeneral method for converting a 2-alkoxyimino arylacetic acid into itsacid chloride without isomerisation described immediately afterpreparation 35:

Syn-2-Butoxyiminophenylacetic acid

Syn-2-Isopropoxyiminophenylacetic acid

Syn-2-Propoxyiminophenylacetic acid

Syn-2-Propoxyimino-(thien-2-yl)acetic acid

Syn-2-Ethoxyimino (benzo[b]-fur-2-yl)acetic acid

Syn-2-Ethoxyimino-(thien-3-yl)acetic acid

PREPARATION 40 2-Phenoxyimino-2-phenylacetic acid (syn- isomer)

A solution of syn-2-hydroxyimino-2-phenylacetic acid (33 g) in drymethanol (500 ml) was treated with 1.105 N sodium methoxide solution(486 ml), and stirred for 15 minutes. To the solution was addeddiphenyliodonium bromide (90 g), and the resulting mixture was stirredfor 18 hours under nitrogen. A small amount of solid was filtered off,and the filtrate was evaporated to dryness. Water (600 ml) and ether(600 ml) were added to the residue, and the pH of the mixture wasadjusted to 7.0 with concentrated hydrochloric acid. The aqueous layerwas washed twice with ether, and then acidified under ether to pH 1.8with concentrated hydrochloric acid. The acid mixture was extracted intoether, and the combined extracts were washed (water, saturated brine),dried, and evaporated to give a dark brown solid (ca 35 g). This solidwas triturated with ice-cold nitromethane. The solid was collected,washed with a little cold nitromethane, and dried in vacuo to give fawncrystals of the title acid (24.41 g, 51 %), m.p. 104.8°-105.1°, λ_(max).(ethanol) 267.5, 285 nm (ε 11,600; 10,100). Similarly were prepared:

PREPARATION 41

2-Phenoxyimino-2-(thien-2-yl)acetic acid (syn-isomer) (52%) m.p.98.3°-99.5°, λ_(max). (ethanol) 267.5, 303 nm. (ε 9,900; 12,000). and

PREPARATION 42

2-Phenoxyimino-2-(fur-2-yl)acetic acid (syn-isomer) (34%), m.p.100.7°-100.9°, λ_(max). (ethanol) (270.5, 292.5 nm (ε 14,300; 15,700).

PREPARATION 43 2-Cyclopentyloxyimino-2-(fur-2-yl)acetic acid(syn-isomer)

Fur-2-ylglyoxylic acid (2.80 g) and cyclopentyloxamine hydrochloride(3.3 g) were dissolved in a mixture of water (100 ml) and ethanol (50ml), and the pH of the solution was adjusted to 5.0. The solution wasstirred for 19 hours, the alcohol was evaporated off, and the solutionwas acidified to pH 1.5 under ethyl acetate. The acid mixture wasextracted into ethyl acetate, and the combined extracts were washed,dried, and evaporated to give the crude acid (4.38 g). This acid wastreated with charcoal in benzene for 15 minutes, filtered, and thefiltrate was evaporated to give a solid, which was recrystallised twicefrom cyclohexane to give the title acid (2.28 g, 51%), m.p. 96.6°-97.7°,λ_(max). (ethanol) 277.5 nm (ε 15,600).

PREPARATIONS 44-50 2-Alkoxyimino-2-arylacetic acids

General Procedures

A mixture of the substituted glyoxylic acid and an excess (10 to 15%) ofthe alkoxyamine hydrochloride was suspended in water or aqueous ethanol,stirred, and the pH of the mixture adjusted to between 4 and 5 withsodium hydroxide solution (N to 10N). A clear solution at pH 4 to 5 wasmaintained during the reaction by further additions of sodium hydroxidesolution and ethanol as needed. The reaction mixture was kept at roomtemperature until all of the keto-acid was consumed (it may be necessaryto add a further portion of the more volatile alkoxyamines). Theprogress of the reaction was followed by acidification of an aliquot,extraction with ethyl acetate and thin layer chromatography of theextract on silica plates (developed with a mixture of chloroform:methanol: acetic acid; 18:2:1). The alkoxyiminoacetic acids were lesspolar than the starting keto-acids. The reaction times were 2 hours to 2days. When reaction was complete the pH of the mixture was adjusted tobetween 7 and 8 and the ethanol (if any) was removed by evaporation. Theaqueous mixture was extracted with ether, the extract discarded and theaqueous phase acidified to pH <2 with dilute hydrochloric acid. Themixture was extracted with ethyl acetate or ether, the extract dried andevaporated to give the crude product which was purified by one of thefollowing methods:

(a) Crystallisation and recrystallisation (if needed) from a suitablesolvent.

(b) The crude product dissolved in ether was treated with a small excessof a solution of diazomethane in ether. The excess reagent was destroyedwith acetic acid and the solution washed with sodium bicarbonatesolution and evaporated to give the crude methyl esters. The esters wereseparated by preparative thick layer chromatography or columnchromatography on silica, and then hydrolysed conventionally with alkalito give the syn acids, which were purified by crystallisation from asuitable solvent.

These methods were employed to prepare the intermediates listed in Table4 (syn-isomers).

                                      Table 4                                     __________________________________________________________________________     ##STR64##                                                                    Prepar-                    Purific-        τ values                                                                          λ.sub.max           ation                      ation           (DMSO-d6)                                                                             nm                         No.     R            R.sup.a                                                                             (solvent)                                                                              Mp°                                                                           R   R.sup.a                                                                           (EtOH)                                                                              ε            __________________________________________________________________________    44                                                                                     ##STR65##                                                                                  ##STR66##                                                                          (b) (cyclohexane)                                                                      71.2   2.30, 2.7- 3.0                                                                    5.25, 7.9- 8.6                                                                    291.5 10,900               45                                                                                     ##STR67##   C(CH.sub.3).sub.3                                                                   (a) (cyclohexane)                                                                      124.5-125.5                                                                          2.1- 2.45, 2.45- 2.85,                                                            8.66                                                                              232.5, 296, 307.5                                                                    6,700; 25,400;                                                               23,500               46                                                                                     ##STR68##   CH.sub.3                                                                            (a) (benzene)                                                                          114-115                                                                              3.03, 3.77, 3.92, 6.16                                                            6.24                                                                              286   16,200               47                                                                                     ##STR69##   C(CH.sub.3).sub.3                                                                   (a) (benzene)                                                                          146-147                                                                              3.00,  3.75, 3.90, 6.16                                                           8.66                                                                              284   16,000               48      Ph                                                                                          ##STR70##                                                                          (b) (cyclohexane)                                                                      93.3   2.49                                                                              5.18 8.0- 8.6                                                                     259   14,000               49                                                                                     ##STR71##   CH.sub.3                                                                            (a) (cyclohexane/ benzene)                                                             84-86  2.68(Ph), 2.78, 3.62, 3.78,                                                   4.32, 5.47                                                                        6.14                                                                              285   12,400               50      Ph           CH.sub.2 CO.sub.2 Bu.sup.t                                                            (a)    88.5   2.47                                                                              5.32                                                                              253   13,800                                          (carbon tetra-      (CH.sub.2)                                                chloride)           8.58                                                                          (Bu.sup.t)                     __________________________________________________________________________

PREPARATION 51 2-(Thien-2-ylmethoxyimino)-(1-methylpyrrol-2-yl)aceticacid (syn-isomer)

A solution of 1-methylpyrrol-2-ylglyoxylic acid (4.6 g) andthien-2-ylmethoxamine hydrochloride (5.46 g) in aqueous ethanol (100 ml,1:1) was adjusted to pH 4.8 with 10N-sodium hydroxide solution andstirred at pH 4.8 for 24 hours at room temperature. A further portion ofthien-2-ylmethoxamine (0.5 g) was added and the solution was maintainedat pH 4.8 and room temperature for a further 2 days. The pH was thenadjusted to 8 with sodium bicarbonate solution and the ethanol wasremoved by evaporation. The aqueous residue was washed with ether andthe aqueous phase was acidified to pH 1.5 under ether with2N-hydrochloric acid. The ether extracts were combined and washed withwater, dried and evaporated to give an orange oil (8.8 g). The crudemixture of syn and anti-isomer was esterified with a slight excess ofdiazomethane in ether.

To a solution of the mixed methyl esters (7.7 g) in methanol (100 ml)was added N-sodium hydroxide (28 ml). The mixture was kept at roomtemperature for 3 hours when thin-layer chromatography of an aliquotshowed only traces of remaining anti-ester. After a further 30 minutes2N-hydrochloric acid (14 ml) was added and the methanol was removed byevaporation. The residue was partitioned between ether and excess sodiumbicarbonate in water. The ether layer was separated, washed with water,dried and evaporated to a pale orange oil (5.9 g).

This oil in methanol (100 ml) was treated with 10N-sodium hydroxidesolution (4.5 ml) and kept at room temperature for 16 hours. A furtherportion of 10N-sodium hydroxide solution (4.5 ml) was added and after 24hours at room temperature the mixture was warmed to 60° for 30 minutes.The methanol was removed by evaporation and the residue divided betweenether and sodium bicarbonate solution. The aqueous phase was acidifiedunder ether with 2N-hydrochloric acid. The combined ether extracts werewashed with water and dried. Evaporation of the ether gave a pale orangeoil (4.8 g) which was crystallised from carbon tetrachloride to give thetitle compound as pale brown crystals (1.9 g); m.p. 70°-71°; λ_(max).(EtOH) 235, 287.5 nm (ε 11,600 and 17,100): τ (DMSO-d₆) values include4.70 (S, CH₂) and 6.18 (S, CH₃).

GENERAL METHOD FOR CONVERTING A 2-SUBSTITUTED OXYIMINO-2-ARYLACETIC ACIDINTO ITS ACID CHLORIDE WITHOUT ISOMERISATION

A solution of the pure syn-2-substituted oxyimino-2-arylacetic acid (1equiv.) in methanol (ca. 2-4 ml/mmole) was treated with sodium methoxide(1 equiv.) in methanol at 0°-25° and the mixture evaporated to give thesodium salt which may be dried by azeotroping with several portions ofbenzene and/or drying in vacuo over phosphorus pentoxide.

The anhydrous sodium salt (1 equiv.) was suspended in dry benzene (ca. 5ml/mmole) containing a few drops of dry dimethylformamide and treatedwith freshly distilled oxalyl chloride (1-2.5 equiv.). The mixture wasstirred at room temperature for 0.5-1 hour and then evaporated to removebenzene. The resulting acid chlorides were not characterised but weredissolved in acetone and used immediately to acylate the appropriatecephalosporin nucleus.

The acids described in Preparations 40-51 were converted into their acidchlorides in this way.

PREPARATION 52 Cyclopentyloxamine hydrochloride

A mixture of bromocyclopentane (14.9 g), N-hydroxyphthalimide (16.3 g),triethylamine (15 ml), and dimethylformamide (30 ml) was stirred for 16hours, then poured into water (500 ml). The oily mixture was extractedwith ethyl acetate, and the combined extracts, after washing (water),drying, and removal of solvent gave a white solid. This solid wasrecrystallised from ethanol to give N-cyclopentyloxyphthalimide (11.37g, 49%); m.p. 81.2°-82.5°; ν_(max). (CHBr₃) include 1780, 1720 cm⁻¹(CO-N-CO), 970 cm⁻¹ (>N-O-<CH); τ values (DMSO-d6) 2.08 (4 Ar-H), 5.12(cyclopentyl 1-H), 8.18 (4-CH₂).

A mixture of N-cyclopentyloxyphthalimide (11 g), 100% hydrazine hydrate(2.6 g), and ethanol (30 ml) was heated under reflux for 5 minutes.Concentrated hydrochloric acid (6 ml) was added to the mixture, whichwas heated under reflux for a further 5 minutes. Water (20 ml) was addedto the mixture, which was cooled to room temperature, and filtered. Thefiltrate was evaporated to dryness, ethanol (50 ml) was added to theresidue, and a small amount of insoluble material was filtered off. Thefiltrate was evaporated to dryness, and the residue was recrystallisedfrom ethanol/ether to give cyclopentyloxamine hydrochloride (6.28 g,96%), m.p. 156.9°.

PREPARATION 53 t-Butoxycarbonylmethoxamine

t-Butyl chloroacetate (13.0 g, prepared according to Org. Synth., Coll.Vol. 4, 263) was added dropwise to a stirred mixture ofN-hydroxyphthalimide (14.2 g), triethylamine (23.0 g), anddimethylformamide (30 ml), and the resulting mixture was stirred for 4hr. The mixture was poured into water (500 ml), and the precipitatedsolid was collected, washed with water, and dried. Recrystallisationfrom ethanol gave N-t-butoxycarbonylmethoxyphthalimide (17.26 g, 72%);m.p. 145.6°; τ values (DMSO-d6) 2.09 (4 Ar-H), 5.28 (CH₂), 8.56(Bu^(t)).

A solution of N-t-butoxycarbonylmethoxyphthalimide (21 g) in methylenechloride (250 ml) was treated with 100% hydrazine hydrate (7.6 ml) inmethanol (15 ml), and the mixture was stirred for 1.5 hr. 5N-Ammoniasolution was added to dissolve the precipitated solid. The organic layerwas separated, and the aqueous layer was further extracted withmethylene chloride. The combined extracts were washed with water, dried,and evaporated to give a pale-yellow solid. To this was added ether, themixture was filtered, and the filtrate evaporated to givet-butoxycarbonylmethoxamine as a pale yellow liquid, (8.88 g, 80%);ν_(max). (Nujol) includes 3330, 3260 cm.⁻¹ (NH₂), 1742 cm.⁻¹(--COOBu^(t)); τ values (DMSO-d6) are 3.75 (--NH₂), 5.96 (CH₂) 8.55(Bu^(t)).

PREPARATION 54 Methyl N-Benzyloxymethylpyrrol-2-ylglyoxylate

Methyl pyrrol-2-ylglyoxylate (306 mg) in diglyme was treated with sodiumhydride (63 mg) and stirred at room temperature for 3 hr.Benzyloxymethyl chloride (376 mg) was added and the mixture stirred atroom temperature for a further 3 hr. The suspension was filtered and thefiltrate evaporated. The residue, in ether, was washed with sodiumbicarbonate solution, water and dried. Evaporation gave the crudeproduct as a brown oil (530 mg). Purification by preparative thin-layerchromatography gave the title compound as a colourless oil (250 mg,46%); τ values (DMSO-d6) include 6.10 (--CH₃), 4.20 (>N-CH₂ -), 5.47(--OCH₂ --), 2.70 (-Ph).

PREPARATION 55 N-Benzyloxymethylpyrrol-2-ylglyoxylic acid

Crude methyl-N-benzyloxymethylpyrrol-2-ylglyoxylate (10 g) in methanol(150 ml) was treated with sodium hydroxide solution (N: 40 ml) at roomtemperature for 1 hr. Thin-layer chromatography showed completehydrolysis. Hydrochloric acid (2N: 20 ml) was added and the methanol wasremoved by evaporation. The residue was shaken with sodium bicarbonatesolution and ether. The aqueous layer was acidified under ether and theether extract was washed with water and dried. Evaporation gave the acidas an orange oil (4.5 g, 55%); this material was used directly to makethe syn-methoxime described in Preparation 49.

PREPARATION 56 syn-Isopropoxyiminophenylacetic acid

A mixture of phenylglyoxylic acid (3.0 g.), isopropoxyaminehydrochloride (2.5 g.), ethanol (100 ml) and water (50 ml) was stirredand adjusted to pH 4.5 to 5 with sodium hydroxide solution (2N). Thesolution was stirred for 5 hr. maintaining the pH at 4.5-5 with furtheradditions of sodium hydroxide solution. The ethanol was removed byevaporation, the aqueous residue acidified and the product collected byextraction with ethyl acetate. Evaporation of the ethyl acetate gave abrown oil (4.2 g.). that was esterified conventionally with diazomethaneto give a mixture of the syn and anti methyl esters of the titlecompound as an oil (4.02 g.).

The mixture of ester (4.0 g) in methanol (60 ml) was treated with sodiumhydroxide solution (2N: 19.0 ml) and kept for 2 hr. at room temperature.The methanol was evaporated and the residue, diluted with water,extracted with ethyl acetate. Evaporation of the dried (MgSO₄) ethylacetate solution gave the crude syn methyl ester (0.82 g.). The ester(0.82 g) in methanol (20 ml) was treated with sodium hydroxide solution(2N: 3.6 ml) and kept at room temperature for 31 hr. Conventionalisolation of acidic material gave the crude syn isomer (0.706 g) whichwas recrystallised from cyclohexane to give the title compound (0.358g.) m.p. 59.5° λ_(max). (EtOH) 258 nm (ε 12,700), τ (DMSO-d₆) valuesinclude 2.47 (phenyl), 5.53 (O-CH<), 8.71 (CH₃).

PREPARATION 57 syn-Propoxyiminothien-2-ylacetic acid

A mixture of thien-2-ylglyoxylic acid (3.12 g), n-propoxyaminehydrochloride (2.8 g.), ethanol (75 ml) and water (75 ml) was adjustedto pH 4.5 to 5 with sodium hydroxide solution (2N) and stirred at roomtemperature. A clear solution at pH 4.5 to 5 was maintained by furtheradditions of base and ethanol as required. After 4 hr. a further portionof n-propoxyamine hydrochloride (1.4 g) was added and the mixturestirred for a further 3 hr. (keeping the pH at 4.5-5) and then keptovernight. The ethanol was evaporated and the residual solution dilutedwith water, acidified and extracted with ethyl acetate. Evaporation ofthe dried (MgSO₄) ethyl acetate solution gave a mixture of the syn andanti forms of the title acid as an oil (4.8 g.).

The mixture of acids was esterified conventionally with diazomethane togive a mixture of the syn and anti methyl ester (3.175 g.).

The mixture of esters in methanol (50 ml.) was treated with sodiumhydroxide solution (2N; 14 ml) for 10 min. at room temperature. Themethanol was removed, rapidly, by evaporation and the residue, in water,extracted with ethyl acetate. Evaporation of the dried (MgSO₄) ethylacetate solution gave the syn methyl ester (0.416 g). The ester inmethanol (10 ml) was treated with sodium hydroxide solution (2N: 1.7 ml)and kept at room temperature for 26 hr. Conventional isolation of acidmaterial gave the title compound as an oil (0.235 g.) τ (DMSO-d₆) valuesinclude 2.28, 2.7-2.9 (thienyl), 5.90 (O-CH₂).

EXAMPLE 13-Acetoxymethyl-7β-(2-methoxyimino-2-phenylacetamido)-ceph-3-em-4-carboxylicacid (syn-isomer)

To a solution of dicyclohexylcarbodiimide (1.15 g.) and t-butyl3-acetoxymethyl-7β-aminoceph-3-em-4-carboxylate (1.83 g.) in drymethylene chloride (30 ml) was added a solution of syn2-methoxyiminophenylacetic acid (1 g.) in dry methylene chloride (15ml.) and the resulting solution was stirred at room temperature for 1.5hours. After filtration the filtrate was washed with 2N hydrochloricacid, water, saturated sodium bicarbonate solution, water dried, andevaporated to an orange froth (2.60 g.). Part of this froth (0.21 g.)was triturated with petroleum spirit (b.p. 60°-80°) producingsyn-t-butyl 3-acetoxymethyl-7β-(2-methoxyimino-2-phenylacetamido)ceph-3-em-4-carboxylate as a solid (0.15 g.), λ_(max). (EtOH) 258 nm. (ε17,400), ν_(max). (CHBr₃) 1784 cm.⁻¹ (β-lactam), τ (CDCl₃) 2.99 (doubletJ 9.0; NH), 2.2-2.7 (multiplet; Ph), 5.97 (singlet; OCH₃) 7.93 (singlet;acetate), 8.48 (singlet; t-butyl).

The remainder of the froth (2.4 g.) was shaken with trifluoroacetic acid(10 ml) at room temperature for 10 minutes, and evaporated to an oil.Ether (˜80 ml) was added, producing a solution, which on standingprecipitatedsyn-3-acetoxymethyl-7β-(2-methoxyimino-2-phenylacetamido)ceph-3-em-4-carboxylicacid as a white solid (1.58 g., 66%), [α]_(D) ²³ + 55° (c, 1.02 indioxan), λ_(max). (pH 6 phosphate buffer) 258 nm. (ε 19,550). ν_(max).(Nujol) 1782 cm.⁻¹ (β-lactam), τ (DMSO-d₆) 0.21 (doublet, J 8.0 Hz; NH),2.3-2.6 (multiplet; Ph), 6.08 (singlet; OCH₃), 7.98 (singlet, acetate).

EXAMPLE 23-Crotonoyloxymethyl-7β-(2-methoxyimino-2-phenylacetamido)ceph-3-em-4-carboxylicacid (syn-isomer).

A suspension of diphenylmethyl7β-amino-3-crotonyloxymethylceph-3-em-4-carboxylate toluene-p-sulphonatesalt (1.0 g) in ethyl acetate (20 ml) was shaken with sodium bicarbonatesolution. The ethyl acetate layer was washed with water and brine, driedand concentrated under reduced pressure. The residue was dissolved inmethylene chloride (10 ml) and dicyclohexylcarbodiimide (0.324 g) wasadded. This solution was treated with 2-methoxyimino-2-phenylacetic acid(syn-isomer) (0.281 g). After 1 hour the mixture was filtered, andconcentrated under reduced pressure. The residue was dissolved in ethylacetate and the solution was washed with 2N-hydrochloric acid, sodiumbicarbonate solution, water and brine, dried and concentrated underreduced pressure. The resulting foam (1.0 g) was dissolved in anisole (2ml) and the solution was treated with trifluoroacetic acid (8 ml). After5 minutes at 20° the solution was concentrated under reduced pressure.The residue was dissolved in ethyl acetate and this solution wasrepeatedly extracted with sodium bicarbonate solution. The combinedextracts were washed with ethyl acetate and then acidified with2N-hydrochloric acid and extracted with ethyl acetate. The extract waswashed with water and brine, dried, concentrated under reduced pressureand added to stirred petroleum to precipitate the title methoxime (0.467g; 67%) [α]_(D) + 37.3° (c 0.9 in DMSO) λ_(max). (pH 6 phosphate buffer)258 nm (ε 17,800), ν.sub. max. (Nujol) 1782 (β-lactam), 1710 (CO₂ H),1680 and 1540 (CONH) and 1660 cm.⁻¹ (unsaturated ester), τ (DMSO-d₆, 100MHz) 0.19 (doublet, J 8 Hz); 3.03 (multiplet; CH═CH-CH₃) 6.06 (singlet;NOCH₃), 6.28 and 6.50 [2 doublets (branches of quartet), J 18 Hz; C-2CH₂ ], and 8.12 (double doublet, J 7 and 1.5 Hz; CH═CH-CH₃).

EXAMPLES 3-11 General Procedures for the Preparation of7β-(2-alkoxyimino-2-substituted-acetamido)-3-(substituted)methylceph-3-em-4-carboxylic acids using Dicyclohexylcarbodiimide

(i) Preparation of Intermediate 4-Carboxylic Acid Esters

Method A

To a solution of a t-butyl or diphenylmethyl ester of7β-amino-3-(substituted)-methylceph-3-em-4-carboxylic acid (1 equiv.)and dicyclohexylcarbodiimide (1-1.2 equiv.) in dry methylene chloride(cosolvents e.g. dimethylformamide or dioxan have been used) was added,at 0°-20°, a solution of the syn 2-alkoxyimino-substituted acetic acid(1 equiv.) in dry methylene chloride. After stirring for 45 min-3 hr. atroom temperature the mixture was filtered, the filtrate was washedsuccessively with 2N-hydrochloric acid, saturated sodium hydrogencarbonate solution, water and brine. The organic phase was dried andevaporated to give the required ester as an oil or foam.

Method B

As above using the dimethyl ether of diethylene glycol in place ofmethylene chloride.

Method C

As Method A with purification of the ester by chromatography on silica.

Method D

As Method A but with prior regeneration of the 7β-amino ester from itsp-toluene-sulphonic acid salt (1 equiv.) by shaking with ethyl acetateand an excess of saturated sodium bicarbonate solution. After washingwith water and brine the organic layer was evaporated to dryness andredissolved in methylene chloride.

(ii) Deprotection of the Intermediate Esters

Method E

The t-butyl or diphenylmethyl ester was dissolved in trifluoroaceticacid (5-10 ml./gm. ester) and left at room temperature for (5-10 min.)then evaporated under reduced pressure. The crude product was taken upin ether or ethyl acetate, extracted into aqueous sodium hydrogencarbonate solution and washed with ethyl acetate. The aqueous layer wasacidified with 2N-hydrochloric acid and extracted into ethyl acetate.The organic layer was washed, dried and evaporated to give the requiredsyn-7β-(2-alkoxyimino-2-substitutedacetamido)-3-(substituted)-methylceph-3-em-4-carboxylic acid.

Method F

The ester was dissolved in anisole (1-5 ml/grm. ester) and treated withtrifluoroacetic acid (4-10 ml./grm. ester) at room temperature for 5-10min. then worked up as described in Method E.

(iii) Preparation of Diphenylmethyl7β-Amino-3-cyclopropylcarbonyloxymethylceph-3-em-4-carboxylatep-toluene-sulphonic acid salt used as Starting Material in Example 11

(a) Diphenylmethyl3-cyclopropylcarbonyloxymethyl-7β-(thien-2-yl)-acetamidoceph-3-em-4-carboxylate

To a stirred solution of diphenylmethyl3-hydroxymethyl-7β-(thien-2-yl)acetamidoceph-3-em-4-carboxylate (8 g.)in dry tetrahydrofuran (20 ml.) containing anhydrous pyridine (6.7 ml.)was added a solution of cyclopropane carbonyl chloride (from the acid,6.7 g. and thionyl chloride at room temperature for 90 mins.) in drytetrahydrofuran (10 ml.) over a period of 10 mins. at room temperature.After stirring at room temperature for 2 hr. the mixture was evaporatedto near dryness and diluted with ethyl acetate (100 ml.). The mixturewas washed successively with sodium hydrogen carbonate solution,2N-hydrochloric acid and water. The organic layer was stirred withcharcoal at room temperature for 1 hr., filtered and the filtrateevaporated to a foam. Trituration with petroleum spirit (bp. 60°-80°)gave the title ester (7.8 g., 87%), [α]_(D) + 28° (c 0.83 in dioxan), λinf. (EtOH) 235, 255 nm (ε 12,800; 7,700), ν_(max). (CHBr₃) 1790(β-lactam), 1728 cm.⁻¹ (esters), τ (DMSO-d₆) values include 0.8 (doubletNH) 3.02 (CHPh₂), 8.4 (multiplet, ##STR72## 9.0 - 9.2 (CH₂ groups in thecyclopropane ring).

EXAMPLE 3

(a) t-Butyl3-methyl-7β-(2-methoxyimino-2-phenylacetamido)-ceph-3-em-4-carboxylate(syn-isomer) was obtained as a yellow solid m.p. 66° (dec.), λ_(max).(EtOH) 255 nm (ε 16,350), ν_(max). (CHBr₃) 1785 (β-lactam), 1720(t-butyl ester), 1690, 1520 cm.⁻¹ (CONH); τ (CDCl₃) 3.02 (doublet J 8.0Hz; NH) 2.3-2.7 (multiplet, Ph), 5.96 (singlet; OCH₃), 7.89 (singlet,CH₃) 8.48, (singlet; t-butyl) by Method A. Deprotection by Method Egave:-

(b) 3-Methyl-7β-(2-methoxyimino-2-phenylacetamido)ceph-3-em-4-carboxylic Acid (syn-isomer), as a cream solid (67%), m.p.145° (dec.), [α]_(D) ¹⁷ + 100° (c 1.32 in dioxan) λ_(max). (pH 6.0phosphate buffer) 258-259 nm (ε 18,650), ν_(max) (Nujol) 1760(β-lactam), 1702 (CO₂ H), 1660, 1536 (CONH); τ (DMSO-d₆) 0.24 (doublet J8.0 Hz; NH), 2.3-2.6 (multiplet; Ph), 6.05 (singlet, OCH₃), 7.94(singlet; CH₃).

EXAMPLE 4

(a) t-Butyl(3-Acetoxymethyl-7β-(2-benzyloxyimino-2-phenylacetamido)ceph-3-em-4-carboxylate(syn-isomer) m.p. 123°-125°, λ_(max) (EtOH) 259 nm (ε 20,500), ν_(max)(CHBr₃) 1796 (β-lactam), 1732 (acetate and ester), 1694, and 1522 cm,⁻¹CONH); τ (CDCl₃) 3.00 (doublet J 9.0 Hz; NH) 2.38, 2.60 (multiplet, Ph),2.60 (benzyl aromatic protons), 4.74 (singlet; methylene group ofbenzyl), 7.94 (singlet, acetate), 8.48 (singlet, t-butyl) was obtainedby Method A. Deprotection by Method E gave:-

(b)3-Acetoxymethyl-7β-(2-benzyloxyimino-2-phenylacetamido)-ceph-3-em-4-carboxylicacid (syn-isomer) as a white solid (58%), m.p. 167° (dec.) [α]_(D) ²⁶ +50.5° (c, 0.85 in dioxan), λ_(max). (pH 6.0 phosphate buffer) 259 nm (ε20,700)., ν_(max). (Nujol) 1771 (β-lactam), 1735, 1252 (acetate), 1650and 1530 cm.⁻¹ (CONH), τ (DMSO-d₆) 0.14 (doublet J 8.0 Hz; NH), 2.3-2.7(multiplet; aromatic protons), 4.79 (singlet, CH₂ of benzyl group), 7.96(singlet, acetate).

EXAMPLE 5

(a) Diphenylmethyl7β-(2-methoxyimino-2-phenylacetamido)-3-methylthiomethylceph-3-em-4-carboxylate(syn-isomer) λ_(max). (EtOH) 259 nm (ν 18,550), β_(max). (CHBr₃) 1785(β-lactam), 1722 (benzhydryl ester), 1688 and 1518 cm.⁻¹ (CONH); τ(CDCl₃) 3.01 (doublet 7 Hz; NH), 2.32, 2.64, 2.65 (aromatic protons)5.97 (singlet; OCH₃), 8.16 (singlet, SCH₃) was prepared by Method A.Subsequent deprotection by Method E gave:-

(b)3-Methylthiomethyl-7β-(2-methoxyimino-2-phenylacetamido)-ceph-3-em-4-carboxylicacid (syn-isomer) as a precipitated solid., (51%), [α]_(D) ²⁶ + 51° (c,0.98 in dioxan), λ_(max). (pH 6.0 phosphate buffer) 259 nm, (ε 18,300),ν_(max). (Nujol) 1781 (β-lactam), 1770 (CO₂ H), 1670 and 1531 cm.⁻¹(CONH); τ (DMSO-d₆) 0.22 (doublet J 9 Hz; NH), 6.06 (singlet OCH₃), 8.01(singlet SCH₃).

EXAMPLE 6

(a) Diphenylmethyl3-Benzoyloxymethyl-7β-(2-methoxyimino-2-phenylacetamido)ceph-3-em-4-carboxylate(syn-isomer) was prepared as a crude orange solid (80%) by Method A.Deprotection by Method F gave:-

(b)3-Benzoyloxymethyl-7β-(2-methoxyimino-2-phenylacetamido)-ceph-3-em-4-carboxylicAcid (syn-isomer) as a white powder (48%) [α]_(D) + 46.5° (c 0.9 inDMSO) λ_(max). (pH 6 phosphate buffer) 232.5 (ε 22,400) and 258.5 nm(ε21.400) ν_(max). (Nujol) 1780 (β-lactam), 1720 and 1265 (benzoate),1705 (CO₂ H), 1675 and 1532 cm⁻¹ (CONH) τ (DMSO-d₆, 100 MHz) 0.16(doublet, J 8 Hz; NH) 4.06 (double doublet J 5 and 8 Hz; C-7H), 4.70(doublet; J5 Hz; C-6 H), 6.03 (singlet; NOCH₃), and 6.14 and 6.44 [2doublets (branches of quartet), J 18 Hz; C-2 CH₂ ].

EXAMPLE 7

(a) Diphenylmethyl3-Isobutyryloxymethyl-7β-(2-methoxyimino-2-phenylacetamido)ceph-3-em-4-carboxylate(syn-isomer) was prepared by Method A and deprotected withoutpurification by Method F to give:-

(b)3-Isobutyryloxymethyl-7β-(2-methoxyimino-2-phenylacetamido)ceph-3-em-4-carboxylicacid (syn-isomer) (73%) [α]_(D) + 48.5° (c 1.0 in DMSO) λ_(max). (pH 6phosphate) 258 nm (ε 18,700), ν_(max). (Nujol) 1783 (β-lactam), 1725(carboxylic ester and acid), 1670 and 1530 cm.⁻¹ (CONH), τ (DMSO-d₆ ;100 MHz) 0.19 (doublet, J 8 Hz; NH) 2.2-2.6 (multiplet; aromaticprotons), 4.09 (double doublet, J 5 and 8 Hz; C-7H), 4.76 (doublet, J 5Hz; C-6 H), 4.94 and 5.26 [2 doublets (branches of quartet), J 13 Hz;C-3 CH₂ ], 6.04 (singlet; NOCH₃), 6.28 + 6.50 [2 doublets (branches ofquartet), J 18 Hz; C-2 CH₂ ], 7.40 (septet, J 7 Hz; CH(CH₃)₂) and 8.80(doublet, J 7 Hz; CH(CH₃)₂).

EXAMPLE 8

(a) t-Butyl3-Acetoxymethyl-7β-[2-methoxyimino-2-(thien-2-yl)-acetamido]-ceph-3-em-4-carboxylate(syn-isomer) was obtained as a solid (85%), λ_(max).^(EtOH) 262-263 nm(ε 14,900), λ_(inf). 280 nm (ε 13,280) ν_(max). (CHBr₃) 3400 (NH); 1780(β-lactam); 1738, 1120 (CO₂ R) and 1684, 1514 cm.⁻¹ (CONH) τ (CDCl₃)2.5-2.7, 2.95 (thienyl protons); 5.97 (OMe); 7.93 (OAc), and 8.48(t-butyl) by Method A. Deprotection by Method E gave the free acid:-

(b)3-Acetoxymethyl-7β-[2-methoxyimino-2-(thienyl-2-yl)-acetamido]-ceph-3-em-4-carboxylicacid (syn-isomer) (56%) [α]_(D) ²³ + 60° (c, 0.8 in dioxan), λ_(max).262 nm (ε 15,700), λ_(inf). 290 nm. (ε 10,700), ν_(max). 3275 (NH); 1768(β-lactam); 1728 (OAc); 1700, 2600 (CO₂ H); and 1648, 1520 cm.⁻¹ (CONH).τ (DMSO-d₆) 2.2-2.9 (thienyl); 6.08 (OMe); 0.13 (NH); 4.12, 4.76(β-lactam); 6.28, 6.52 (J = 18 Hz. CH₂ in ring); 4.94, 5.27 (J = 13 Hz.CH₂ OAc), and 7.94 (OAc).

EXAMPLE 9

(a) t-Butyl3-Acetoxymethyl-7β-(2-t-butoxyimino-2-phenylacetamido)-ceph-3-em-4-carboxylate(syn-isomer) was prepared by Method B and purified by chromatography onsilica, Method C to give a pale yellow foam (43%) which was crystallisedfrom isopropyl ether to give the ester, m.p. 150°-153°, τ (CDCl₃)2.2-2.75 (multiplet, aromatic protons), 2.83 (doublet, NH), 8.61(t-butoximine), 8.46 (t-butyl ester). Deprotection by Method F gave

(b)3-Acetoxymethyl-7β-(2-t-butoxyimino-2-phenylacetamido)ceph-3-em-4-carboxylicAcid (syn-isomer) as a pale yellow foam, ν_(max). (CHBr₃) 1782(β-lactam) 1685, 1522 cm.⁻¹ (CONH), τ (DMSO-d₆) 2.2-2.75 (multiplet,aromatic protons), 0.4 (doublet, NH), 8.70 (t-butoxime).

EXAMPLE 10

(a) t-Butyl3-Acetoxymethyl-7β-[2-methoxymethoxyimino-2-(thien-2-yl)acetamido]-ceph-3-em-4-carboxylate(syn-isomer)λ_(max). (EtOH) 260 nm (ε 12,940), ν_(max). (CHBr₃) 1778(β-lactam), 1688 and 1510 cm.⁻¹ (CONH), τ (CDCl₃) 2.74 (doublet, NH),4.76 (--OCH₂ OCH₃), 6.49 (OCH₂ OCH₃), 7.91 (OCOCH₃), 8.44 (Bu^(t)), wasprepared by Method A and then treated with trifluoroacetic acid byMethod E to give:-

(b)3-Acetoxymethyl-7β-[2-methoxymethoxyimino-2-(thien-2-yl)-acetamido]-ceph-3-em-4-carboxylicAcid (syn-isomer), [α]_(D) + 51° (c 0.8, DMSO), λ_(max). (pH 6 phosphatebuffer) 262.5 nm (ε 16,400), ν_(max). (Nujol) 1778 (β-lactam), 1670,1530 cm.⁻¹ (CONH), τ (DMSO-d₆) 0.11 (doublet; NH), 4.89 (OCH₂ OCH₃),6.62 (OCH₂ OCH₃), 7.96 (OCOCH₃).

EXAMPLE 11

(a) Diphenylmethyl3-Cyclopropylcarbonyloxymethyl-7β-(2-ethoxyimino-2-phenylacetamido)ceph-3-em-4-carboxylate(syn-isomer)λ_(max). (EtOH) 256.5 nm (ε 15,800) ν_(max). (CHBr₃) 1780 (β-lactam),1680, 1510 (CONH), 1720 cm.⁻¹ (esters), τ (DMSO-d₆) values include 0.19(doublet, NH), 3.01 (CHPh₂), 5.76 (CH₂ CH₃), 8.68 (CH₃), 8.35 (multiplet##STR73## 9.2 (CH₂ groups in cyclopropane ring) was prepared by Method Cand then deprotected by Method F to give

(b)3-Cyclopropylcarbonyloxymethyl-7β-(2-ethoxyimino-2-phenylacetamido)ceph-3-em-4-carboxylicAcid (syn-isomer), [α]_(D) +75°, (c 0.86 dioxan) λ_(max). (pH 6phosphate buffer) 257 nm (ε 16,000), ν_(max). (Nujol) 1780 cm.⁻¹(β-lactam) τ (DMSO-d₆) values include 0.25 (doublet NH), 5.80 (CH₂ CH₃),8.73 (CH₃).

EXAMPLE 123-Acetoxymethyl-7β-(2-methoxyimino-2-phenylacetamido)ceph-3-em-4-carboxylicacid (syn-isomer).

To a cold (0°-5°) solution of3-acetoxymethyl-7β-aminoceph-3-em-4-carboxylic acid (0.565g.) in acetone(10 ml) and water (10 ml) containing anhydrous sodium bicarbonate (0.42g) was added a solution of syn-2-methoxyiminophenylacetyl chloride(0.495 g.) in acetone (5 ml) over a period of 5 minutes. The solutionwas stirred at room temperature for 30 minutes and then evaporated toremove acetone. The solution was washed with ether (20 ml), and theaqueous phase acidified under ethyl acetate (50 ml) to pH 2 with2N-hydrochloric acid. The mixture was filtered and the layers separated;the aqueous phase was extracted with ethyl acetate. The organic extractswere combined, dried and evaporated to give a white solid (0.48 g.).This was triturated with ether, producing the title compound (0.45 g.64%), [α]_(D) ¹⁷ + 56° (1.04 in dioxan), λ_(max). (pH 6 phosphatebuffer) 259 nm (ε 19,700), ν_(max). (Nujol) 1778 (β-lactam), 1740, 1262(OCOCH₃) 1712 (CO₂ H), 1660, 1534 cm.⁻¹ (CONH): τ(DMSO-d₆) valuesinclude 0.2 (doublet, J 8.0 Hz; NH), 2.3-2.6 (multiplet; Ph), 6.05(singlet; OCH₃), 7.94 (singlet, acetate).

EXAMPLE 133-Acetoxymethyl-7β-(2-ethoxyimino-2-phenylacetamido)-ceph-3-em-4-carboxylicacid (synisomer)

oxalyl chloride (0.26 ml.) was added to a suspension of sodiumsyn-ethoxyiminophenylacetate [prepared from the corresponding acid (300mg.) and 0.43N sodium methoxide solution (3.62 ml.), and dried overphosphorus pentoxide] in dry benzene (20 ml.) containing one drop ofdimethylformamide. After stirring for 1 hour, the mixture was evaporatedto dryness at room temperature. The residue was dissolved in acetone (15ml.), and this solution was added dropwise to an ice-cooled, stirredsolution of 7β-aminocephalosporanic acid (424 mg.), in water (20 ml.)containing sodium bicarbonate (262 mg.). The mixture was stirred for 2hr., then the acetone was evaporated and the aqueous solution wasacidified to pH 1.5. This mixture was extracted with ethyl acetate, theextracts were combined, washed (water, brine) and dried. Evaporation ofthe extracts gave the title compound (622 mg., 89%) as a colourlessfoam, [α]_(D) + 56° (c 1.04 dioxan), λ_(max). (pH 6 phosphate buffer),257.5 nm (ε 20,200), ν_(max). (Nujol) 1772 (β-lactam), 1656 and 1518cm.⁻¹ (CONH), τ values (DMSO-d₆) include 0.23 (doublet, J 8 Hz, NH),2.3-2.6 (multiplet, aromatic protons), 5.75 (quartet, CH₂ CH₃), 8.68(triplet, CH₂ CH₃). 7.96 (OCOCH₃).

EXAMPLE 143-Acetoxymethyl-7β-(2-t-butoxyiminothien-2'-ylacetamido)ceph-3-em-4-carboxylicAcid (syn isomer)

Methanolic sodium methoxide (0.53 N, 7.5 ml) was added dropwise to astirred solution of syn-t-butoxyimino-thien-2-ylacetic acid (0.9 g.) indry methanol (10 ml.) at 0°-5°. The mixture was evaporated to removemethanol and dried by azeotroping with dry benzene. Oxalyl chloride(0.63 ml., 0.95 g.) was added to a stirred suspension of the sodium saltand dimethylformamide (3 drops) in dry benzene (40 ml.). The mixture wasstirred at room temperature for 1 hr. and evaporated to remove benzene.The acid chloride in acetone (10 ml.) was added dropwise to a stirredsolution of 7β-aminocephalosporanic acid (1.09 g.) and sodiumbicarbonate (0.672 g.) in acetone (20 ml.) and water (20 ml.) at 0°-5°and the mixture was stirred at room temperature for 2 hr. The resultingsolution was evaporated to remove acetone and washed with ethyl acetate.The aqueous solution was acidified, in the presence of ethyl acetate,with 2N hydrochloric acid to pH 1.5 and extracted with ethyl acetate.The combined extracts were washed with water, dried and evaporated togive the title compound (1.15 g., 61%) as a pale yellow foam,[α]_(D).sup.≦ + 61° (c 1.0, dioxan), λ_(max). (pH 6 phosphate buffer)260 nm (ε 12,500), ν_(max). (Nujol) 1780 (β-lactam) 1666 and 1520 cm.⁻¹(CONH) τ values (DMSO-d₆) include 0.28 (doublet, J 8 Hz; NH), 2.36 (1H)and 2.84 (2H) (thien-2-yl protons), 7.98 (OAc), 8.68 (Bu^(t)).

EXAMPLE 153-Acetoxymethyl-7β-(2-t-butoxyiminobenzo[b]-thien-3'-ylacetamido)ceph-3-em-4-carboxylicAcid (syn-isomer)

syn-t-Butoxyiminobenzo-[b]-thien-3-ylacetic acid (0.976 g.) was treatedwith sodium methoxide solution (0.445 M:6.1 ml) at room temperature.Evaporation gave the sodium salt as a white powder (1.05 g.). This wasdried over phosphorus pentoxide overnight.

The sodium salt (0.5 g.) suspended in dry benzene (10 ml) containingdimethylformamide (1 drop) was treated at room temperature with oxalylchloride (0.4 ml) for 1 hr. The solvent was removed by evaporation andthe residue in acetone (20 ml) was added dropwise to a solution of7β-aminocephalosporanic acid (0.49 g.) and sodium bicarbonate (0.378 g.)in water (30 ml) at 0°-5°. The resulting pale yellow suspension wasstirred at room temperature for 21/2 hr. The acetone was removed byevaporation and the aqueous phase was acidified to pH 2 under ether. Theether fraction was washed with water and dried. Evaporation gave acream-coloured foam that was dissolved in methylene chloride andreevaporated to give, after drying, the title compound (0.85 g. 95%).[α]_(D) + 61° (c 1 dioxan), λ_(max). (pH 6 buffer) 230, 297, 304 inf. nm(ε 27,600, 11,500, 10,630), τ (DMSO-d₆) values include 0.29 (doublet,NH), 4.04 (double doublet, 7 proton), 4.73 (doublet, 6-proton), 8.59(Bu^(t)).

EXAMPLE 163-Acetoxymethyl-7β-(2-t-butoxyiminofur-2'-ylacetamido)ceph-3-em-4-carboxylicAcid (syn-isomer)

syn-t-Butoxyiminofur-2-ylacetic acid (2.11 g.) was treated at roomtemperature with sodium methoxide (0.525 M:19.1 ml). The methanol wasremoved by evaporation and the resulting buff powder was dried overphosphorus pentoxide overnight. The sodium salt (933 mg.) in dry benzene(10 ml) containing dimethylformamide (1 drop) was treated with oxalylchloride (0.8 ml) at room temperature for 1 hr. The solvent was removedby evaporation and the residue in acetone (30 ml) was added dropwise toa solution of 7β-aminocephalosporanic acid (1.09 g) and sodiumbicarbonate (672 mg.) in water (50 ml) at 0°-5°. The resulting solutionwas stirred at room temperature for 11/2 hr. The acetone was removed byevaporation and the aqueous phase was adjusted to pH 8 and washed with alittle ether. The aqueous layer was acidified to pH 2.0 under ether andthe organic layer was washed with water, dried and evaporated to give apale yellow foam. This was dried over silica and potassium hydroxidepellets to give the title compound as a pale yellow foam (1.6 g. 86%),[α]_(D) + 62° (c 1 dioxan). λ_(max). pH 6 phosphate buffer) 272 nm (ε18,600), ν_(max). (CHBr₃) 1780 (β-lactam) 1674 and 1510 cm.⁻¹ (CONH), τ(DMSO-d₆) values include 0.34 (doublet, NH), 2.17 and 3.34 (fur-2-yl,protons) 8.71 (Bu^(t)).

EXAMPLE 173-Azidomethyl-7β-(2-benzyloxyiminophenylacetamido)-ceph-3-em-4-carboxylicAcid (syn-isomer)

syn-Benzyloxyiminophenylacetic acid (1.28 g.) was treated at roomtemperature with 0.525 molar sodium methoxide solution (9.55 ml). inmethanol. Evaporation gave the sodium salt as a white powder.

The sodium salt, suspended in dry benzene (15 ml.) containingdimethylformamide (2 drops) was treated with oxalyl chloride (0.51 ml.)and kept at room temperature for 1 hr. After filtration through a drysinter the filtrate was evaporated and the residue in dry methylenechloride (20 ml.) added to a solution of7β-amino-3-azidomethylceph-3-em-4-carboxylic acid (1.27 g.) andtriethylamine (2.07 ml.) in dry methylene chloride (50 ml.) at 0°-5°.The resulting pale orange solution was stirred at room temperature for11/4 hr. Evaporation gave a brown foam which was dissolved in water,washed with a little ether and acidified to pH 1.8 under ethyl acetate.The ethyl acetate gave the crude product as a yellow foam (1.9 g., 77%).Precipitation from sodium bicarbonate solution (50 ml.) with dilute acidgave the title compound (1.4 g., 56%). [α]_(D) + 49.5° (c 1 dioxan)λ_(max). pH 6 phosphate buffer) 258.5 nm (ε 19,400) ν_(max). (CHBr₃)1782 (β-lactam) 1684 and 1512 cm.⁻¹ (CONH). τ values (DMSO-d₆) include0.07 (doublet, J 8 Hz; NH), 2.58 (multiplet, aromatic protons), 4.76(CH₂ Ph), 4.05 (double doublet, C 7 proton).

EXAMPLE 18 Sodium3-azidomethyl-7β-(2-methoxyimino-2-phenylacetamido)ceph-3-em-4-carboxylate(syn-isomer).

To a cold (0°-5°) solution of 3-azidomethyl-7β-aminoceph-3-em-4-carboxylic acid (4.6 g.) in acetone(100 ml) and water (100 ml) containing sodium bicarbonate (3.66 g.), wasadded dropwise over 20 minutes a solution of syn2-methoxyiminophenylacetyl chloride (4.32 g.) and the resulting yellowsolution was stirred at room temperature for 30 minutes. Acetone wasremoved by evaporation, and the dark green solution was washed withether. The pH of the aqueous phase under ethyl acetate (100 ml) wasreduced to 2 with 2N-hydrochloric acid. The layers were separated, andthe aqueous phase was extracted with ethyl acetate. The organic extractswere combined, dried, and evaporated to a pale brown froth (8.2 g.)which was triturated with petroleum spirit (b.p. 60°-80°) anddecolourised with charcoal, producing a cream froth (7.67 g.).

This was dissolved in ethyl acetate (30 ml), and a 10% w/v solution ofsodium 2 -ethyl hexanoate in n-butanol (34.8 ml). was added dropwise tothe stirred solution, precipitating the title compound (4.05 g, 51%),[α]_(D) ²³ + 63.5° (c, 1.0 in water), λ_(max). (pH 6.0 phosphate buffer)258-259 nm. (ε 18,850), ν_(max). (Nujol) 2101 (N₃), 1756 (β-lactam),1596 (CO₂ ⁻), 1682 and 1528 cm.⁻¹ (CONH); τ (DMSO-d₆) values include0.22 (doublet J 8 Hz; NH), 2.3-2.6 (multiplet, Ph) and 6.04 (singlet,OCH₃).

EXAMPLE 19-46 General Procedures for the Preparation of3-Substituted-methyl-7β-(2-substitutedoxyimino-2-arylacetamido)-ceph-3-em-4-carboxylic Acids

Method A

A solution of the appropriate syn-2-substituted-oxyimino-2-arylacetylchloride (prepared from 1 equiv. of the corresponding sodium salt withoxalyl chloride) was dissolved in acetone and the solution was addeddropwise to a stirred, ice-cold (0°-5°) solution of7β-aminocephalosporanic acid or3-azidomethyl-7β-aminoceph-3-em-4-carboxylic acid (1 equiv.) in watercontaining sodium bicarbonate (2-2.5 equiv.). The mixture was stirredfor 30 min.-2.5 hr. allowing the temperature to rise to roomtemperature. Acetone was removed by evaporation under reduced pressure,the pH was adjusted to 1.5-2.0 and the product was extracted into ethylacetate (or occasionally ether). The extracts were washed with water orsaturated brine, dried and evaporated to a foam or a solid.

Method B

As in Method A but the product was purified by dissolving in aqueoussodium bicarbonate and reprecipitated by acidification.

Method C

As in Method A but the sodium salt was extracted into ethyl acetate andthe extract washed successively with 2N-hydrochloric acid and water,dried and evaporated to a foam.

Method D

A solution of the appropriate acid chloride (1 equiv.) was dissolved indry methylene chloride (ca. 5 ml/mmole) and the solution was added to asuspension or a solution of 7β-aminocephalosporanic acid or3-azidomethyl-7β-aminoceph-3-em-4-carboxylic acid (1 equiv.) andtriethylamine (3 equivs.) in methylene chloride at 0°-5°, After stirringat room temperature for 1-1.5 hr. the solution was evaporated todryness, dissolved in water, washed with ethyl acetate and the aqueouslayer acidified to pH 1.5 under ethyl acetate. The ethyl acetate extractwas washed with water and saturated brine and evaporated to a foam orsolid.

                                      TABLE 2                                     __________________________________________________________________________     ##STR74##                                                                                                         β-lactam                                                    [α].sub.D                                                                   pH 6     ν.sub.max.                                                                       τ values for DMSO-d.sub.6                                                 at                                 Ex.                  Me-                                                                              (dio-                                                                             λ.sub.max.                                                                      cm..sup.-1                                                                          100 MHz         Yield              No.                                                                              R        R.sup.a  thod                                                                             xan)                                                                              nm   ε                                                                         (solvent)                                                                           x  R.sup.a y    %                  __________________________________________________________________________    19 Ph       C(CH.sub.3).sub.3                                                                      D  +75°                                                                       256  19,100                                                                            1775  0.39                                                                             8.63    4.07 70                                                      (Nujol)                                  20 Ph                                                                                      ##STR75##                                                                             A  +44°                                                                       251.5                                                                              12,900                                                                             1760 (Nujol)                                                                       0.16                                                                             4.63 (CH.sub.2) 2.50, 2.76                                                    2.93 (thien- 2-yl)                                                                    4.10 71                 21                                                                                ##STR76##                                                                             CH.sub.3 A  +60°                                                                       262  15,200                                                                            1768 (Nujol) 1780 (CHBr.sub.3)                                                      0.13                                                                             6.08    4.12 76                 22                                                                                ##STR77##                                                                             C.sub.2 H.sub.5                                                                        A  +88°                                                                       262.5                                                                              16.600                                                                            1768 (Nujol)                                                                        0.19                                                                             5.82 (CH.sub.2) 8.75                                                          (CH.sub.3)                                                                            4.12 77                 23                                                                                ##STR78##                                                                             n-C.sub.4 H.sub.9                                                                      A  +55°                                                                       262.5                                                                              16,500                                                                            1762  (Nujol) 0.18                                                                  5.86, 8.2-8.8 and 9.06                                                        (CH.sub.2).sub.3 CH.sub.3                                                        4.11    87                      24                                                                                ##STR79##                                                                              ##STR80##                                                                             A  +64° (DMSO)                                                                260.5                                                                              16,300                                                                            1776 (Nujol)                                                                        0.16                                                                             8.6 (CH.sub.3 ) 8.84                                                          (CH.sub.2 CH.sub.3) 4.66                                                      (CHCH.sub.3)                                                                          4.10 54                 25                                                                                ##STR81##                                                                             CH.sub.2 CH.sub.2 Br                                                                   A  +53°                                                                       262.5                                                                              15,500                                                                            1778 (Nujol)                                                                        0.14                                                                             5.59 (OCH.sub.2) 6.30                                                         (CH.sub.2 Br)                                                                         4.10 93                 26                                                                                ##STR82##                                                                             CH.sub.2 Ph                                                                            D  +58°                                                                       262.5 293                                                                          16,000 12,000                                                                     1770 (Nujol)                                                                        0.08                                                                             4.79 (CH.sub.2) 2.58                                                                  4.11 60                 27                                                                                ##STR83##                                                                              ##STR84##                                                                             A  +50°                                                                       242 260 294.5                                                                      17,700 17,300 12,100                                                              1762 (Nujol)                                                                        0.04                                                                             4.63 (CH.sub.2)                                                                       4.09 94                 28                                                                                ##STR85##                                                                              ##STR86##                                                                             A  +36°                                                                       260  18,200                                                                            1786 (Nujol)                                                                        -0.12                                                                            4.78 (CH.sub.2) 1.44, 2.16                                                    2.50 and 2.85 (pyrid-                                                                 4.11)                                                                              63                 29                                                                                ##STR87##                                                                             CH.sub.2 Ph                                                                            A  +52°                                                                       262  23,200                                                                            1768 (Nujol                                                                         0.14                                                                             4.77 (CH.sub.2) 2.57                                                                  4.08 96                 30                                                                                ##STR88##                                                                             CH.sub.3 A  +50°                                                                       260 292                                                                            13,000  7,600                                                                     1762 (Nujol)                                                                        0.09                                                                             5.95    4.12 79                 31                                                                                ##STR89##                                                                             C(CH.sub.3) .sub.3                                                                     C  +35°                                                                       296   8,600                                                                            1780 (Nujol)                                                                        0.26                                                                             8.59    4.09 80                 32                                                                                ##STR90##                                                                             CH.sub.2 Ph                                                                            C  +40°                                                                       290 (infl.)                                                                         8,200                                                                            1778 (Nujol)                                                                        0.00                                                                             4.67 (CH.sub.2)                                                                       4.10 95                 33                                                                                ##STR91##                                                                             CH.sub.3 A  +51.5°                                                                     226 298.5                                                                          28,300 10,800                                                                     1788 (CHBr.sub.3)                                                                   0.2                                                                              5.97    4.11 77                 34                                                                                ##STR92##                                                                             CH.sub.2 Ph                                                                            C  +49°                                                                       225 --                                                                             1760  (CHBr.sub.3)                                                                0.06  4.62 (CH.sub.2)                                                                  4.13    33                      35                                                                                ##STR93##                                                                             CH.sub.3 A  +54°                                                                       273  18,100                                                                            1784 (CHBr.sub.3)                                                                   0.16                                                                             6.07    4.13 50                 36                                                                                ##STR94##                                                                             CH.sub.2 Ph                                                                            A  +51°                                                                       275.5                                                                              19,000                                                                            1790 (CHBr.sub.3)                                                                   0.16                                                                             4.83 (CH.sub.2) 2.64                                                                  4.16 85                 37                                                                                ##STR95##                                                                             CH.sub.2 Ph                                                                            A  +55°                                                                       231 254 306.5                                                                      -- -- --                                                                          1778 (CHBr.sub.3)                                                                   -0.08                                                                            4.68 (CH.sub.2) 2.50                                                                  4.00 85                 38                                                                                ##STR96##                                                                              ##STR97##                                                                             B  +53°                                                                       275  18,200                                                                            1782 (Nujol)                                                                        0.17                                                                             4.86 (CH.sub.2) 2.32; 3.4-                                                    3.6 furyl protons                                                                     4.18 87                 39                                                                                ##STR98##                                                                             C.sub.2 H.sub.5                                                                        A  +59.5°                                                                     274  19,300                                                                            1790 (CHBr.sub. 3)                                                                  5.79; 8.72                                                                       4.11    73                      40                                                                                ##STR99##                                                                             CH.sub.3 A  +58 230 253.5 305                                                                      20,800 18,450 20,800                                                              1790 (CHBr.sub.3)                                                                   -0.04                                                                            5.97    4.00 78                 41                                                                                ##STR100##                                                                            C(CH.sub.3).sub.3                                                                      A  +44.5                                                                             230 254 303                                                                        20,900 15,200 22,200                                                              1780 (CHBr.sub.3)                                                                   0.12                                                                             8.61    4.00 83                 __________________________________________________________________________

                                      TABLE 3                                     __________________________________________________________________________     ##STR101##                                                                                            pH 6      β-lactam                                                                        τ values for DMSC-d.sub.6       Ex.                 [α].sub.D                                                                    λ.sub.max.                                                                       ν.sub.max. cm..sup.-1                                                             at 100 MHz       Yield              No.                                                                              R     R.sup.a                                                                             Method                                                                             (dioxan)                                                                           nm   ε                                                                          (solvent)                                                                            x   R.sup.a  y   %                  __________________________________________________________________________    42 Ph    C(CH.sub.3).sub.3                                                                   D    + 56°                                                                       258  18,300                                                                             1785   0.38                                                                              8.65     4.07                                                                              30                                                    (Nujol)                                    43                                                                                ##STR102##                                                                         CH.sub.3                                                                            D    + 53°                                                                       262  14,600                                                                             1780 (CHBr.sub.3)                                                                    0.09                                                                              6.10     4.10                                                                              55                 44                                                                                ##STR103##                                                                         C.sub.2 H.sub.5                                                                     B    + 58°                                                                       263  15,600                                                                             1770 (Nujol)                                                                         0.13                                                                              5.83 8.74                                                                         (CH.sub.2) (CH.sub.3)                                                              4.09                                                                              59                 45                                                                                ##STR104##                                                                         C(CH.sub.3).sub.3                                                                   B    + 62°                                                                       262 288                                                                            12,200 13,400                                                                      1780 (Nujol)                                                                         0.25                                                                              8.68     4.07                                                                              50                 46                                                                                ##STR105##                                                                         CH.sub.2 Ph                                                                         D    + 48°                                                                       263  15,800                                                                             --     0.05                                                                              4.79 2.60                                                                         (CH.sub.2) (Ph)                                                                    4.12                                                                              11                 __________________________________________________________________________

EXAMPLE 477β-(2-Benzyloxyiminothien-2'-ylacetamido)-3-(2-methyl-1,3,4-thiadiazol-5-ylthiomethyl)ceph-3-em-4-carboxylicacid (syn isomer)

Oxalyl chloride (0.45 ml) was added to a stirred suspension of sodiumsyn-benzyloxyiminothien-2-ylacetate (0.747 g.) in dry benzene (20 ml.)containing dimethylformamide (one drop). The mixture was stirred for onehour, then evaporated to dryness. A solution of the residue in ethylacetate (25 ml.) was added dropwise to a stirred suspension ofdiphenylmethyl7β-amino-3-(2-methyl-1,3,4-thiadiazol-5-ylthiomethyl)ceph-3-em-4-carboxylate(1.35 g.) in ethyl acetate (20 ml), containing propylene oxide (1.0ml.). The solid rapidly dissolved, and the resulting solution wasstirred for 16 hr. The solvent was evaporated off, and the residue wasredissolved in ethyl acetate (50 ml.). This solution was washedsuccessively with 3% sodium bicarbonate solution, 2N hydrochloric acid,water, and saturated brine, dried, and evaporated to dryness to give thetitle compound as its diphenylmethyl ester (2.01 g.), as a pale brownfoam, τ values include (DMSO-d₆) 0.03 (doublet, NH), 4.79 (CH₂ Ph) 7.26(CH₃).

To this crude ester (1.67 g.) was added anisole (0.24 g.), andtrifluoroacetic acid (10 ml.). The resulting solution was left at roomtemperature for 10 min. then the trifluoroacetic acid was removed byevaporation at room temperature. The residue was distributed betweenethyl acetate and aqueous sodium bicarbonate solution. The aqueous layerwas acidified to pH 1.7 then extracted thrice with ethyl acetate. Thecombined extracts were washed (water, saturated brine), dried, andevaporated to dryness to give a red foam (1.04 g.). The foam wasdissolved in aqueous sodium bicarbonate solution, then reprecipitated byaddition of 2N hydrochloric acid. This was repeated to give the titlecompound (350 mg. 28%) [α]_(D) - 96° (c 0.97 dioxan), λ_(max). (pH 6buffer) 274 nm (ε 18,500), ν_(max). (Nujol) 1784 (β-lactam) τ valuesinclude (DMSO-d₆) 0.07 (doublet, NH), 2.60 (Ph), 4.81 (CH₂ Ph) and 7.32(CH₃).

EXAMPLE 48 (a) t-Butyl3-acetoxymethyl-7β-(2-methoxyiminopyrid-3'-ylacetamido)-ceph-3-em-4-carboxylate(syn-isomer)

A suspension of 2-methoxyiminopyrid-3'-ylacetic acid (1.8 g.) indichloromethane (50 ml.) was cooled to ca. -10° and treated withphosphorus pentachloride (2.08 g.). The mixture was stirred andmaintained at ca. -10° for 11/2 hours by which time most of thesuspension had dissolved. The cold mixture was treated with t-butyl7β-amino-3-acetoxymethylceph-3-em-4-carboxylate (3.0 g.) and propyleneoxide (2 ml) and stirred for a further 30 minutes. The solution waspartitioned between ethyl acetate and saturated sodium bicarbonatesolution and extracted with ethyl acetate. The combined organic extractswere washed with water and then extracted with 2N hydrochloric acid.Unchanged amine was removed by the addition of an excess of sodiumnitrite to the cooled acidic extract followed by washing with ethylacetate after ca. 5 minutes at 0°. The resulting aqueous phase wasneutralised with saturated sodium bicarbonate solution and extractedwith ethyl acetate. The organic extract was washed with water, driedover magnesium sulphate and evaporated to give a mixture of the syn- andanti-isomers of the title compound as a foam (1.33 g.).

Chromotography on silica gel using chloroformmethanol (99:1) gave theanti-isomer (394 mg.) followed by the syn-isomer as a foam (683 mg.).The syn-isomer was dissolved in ethyl acetate and precipitated by addingto petroleum spirit bp. 40°-60°. The amorphous solid was collected,washed with petroleum spirit and dried to yield the title ester (484mg., 10%), [α]_(D) ²⁰ + 49° (c 0.45, DMSO), λ_(max). (EtOH) 255 nm (ε16,100), ν_(max). (CHBr₃) 3396 (NH), 1786 (β-lactam), 1735 (OAc), 1724(CO₂ R), 1682 and 1518 cm.⁻¹ (CONH), τ (d₆ DMSO) 0.14 (d, J 8 Hz; NH),1.26, 1.30, 2.03 and 2.48 (multiplets; aromatic protons), 4.10 (q, J 5and 8 Hz; C-7H), 4.74 (d, J 5 Hz; C-6H), 5.03 and 5.36 (2 d, J 13 Hz;C-3 CH₂), 6.03 (s; OCH₃), 6.28 and 6.52 (2d, J 18 Hz; C-2 H₂), 7.97 (s;OCOCH₃), 8.52 (s; C(CH₃)₃).

(b)3-Acetoxymethyl-7β-(2-methoxyiminopyrid-3'-ylacetamido)-ceph-3-em-4-carboxylicacid trifluoroacetic acid salt (syn-isomer)

A solution oft-butyl-3-acetoxymethyl-7β-(2-methoxyiminopyrid-3-ylacetamido)-ceph-3-em-4-carboxylatesyn-isomer (440 mg.), in trifluoroacetic acid (7 ml.) was stood at 20°for 15 minutes. The solvent was removed and the residue evaporated threetimes from benzene. The resulting gum was dissolved in a small volume ofacetone and added slowly to an excess of stirred petroleum spirit (bp40°-60°). The solid was collected by filtration, washed well withpetroleum spirit and dried to afford the title syn acid salt as asolvated pale yellow powder (561 mg.), [α]_(D) ²⁰ + 30° (c 0.88, DMSO),λ_(max). (pH 6 buffer) 254 nm (ε 14,300), ν_(max). (Nujol) 3250 (NH),2600 and 1720 (CO₂ H), 1782 (β-lactam), 1736 (OAc), 1670 (CF₃ CO₂ ⁻),1670 and 1550 cm.⁻¹ (CONH), τ (d₆ -DMSO) 0.08 (d, J 8 Hz; NH), 1.16,1.22, 1.90 and 2.36 (multiplets; aromatic protons), 4.06 (q, J 5 and 8Hz; C-7H), 4.73 (d, J 5 Hz; C-6H), 4.93 and 5.26 (2 d, J 13 Hz; C-3CH₂), 5.98 (s; OCH₃), 6.26 and 6.49 (2d, J 18 Hz; C-2 H₂), 7.94 (s;OCOCH₃).

EXAMPLE 497β-(2-Methoxyimino-2-phenylacetamido)-3-pyridiniummethyl-ceph-3-em-4-carboxylate(syn-isomer)

A solution of3-acetoxymethyl-7β-(2-methoxyimino-2-phenylacetamido)ceph-3-em-4-carboxylicacid (syn-isomer) (5 g.) in water (30 ml), acetone (30 ml) and pyridine(2.8 ml.) was heated at 50° for 4 hours. More pyridine (2.8 ml) wasadded, and the solution (pH ˜ 5) was heated at 50° for 16 hours. Thedark brown solution was decanted from a gum, evaporated to removeacetone, and washed with methylene chloride. Excess solvent was removedby evaporation, and the solution passed down a column of Dowex 1 ionexchange resin in the acetate cycle and the column eluted with water.The eluate was freeze dried, and the solid was triturated with acetone,producing the title compound as a cream solid (0.84 g), [α]_(D) ²³ -6.4° (c, 0.94 in water), λ_(max). (pH 6.0 phosphate buffer) 257 nm (ε19,900), ν_(max). (Nujol) 1770 (β-lactam), 1660, 1540 (CONH) and 1604cm.⁻¹ (CO₂ ⁻); τ (D₂ O) values include 1.03, 1.90 and 1.40 (α, β andγ-protons in the pyridinium ring), 2.2-2.6 (multiplet, Ph), 5.99(singlet, OCH₃), τ (DMSO-d₆) values include 0.27 (doublet, J 8 Hz; NH),6.10 (singlet, OCH₃).

EXAMPLE 50 7β-(2-Methoxyimino-2-phenylacetamido)-3-(4-carbamoylpyridiniummethyl)-ceph-3-em-4-carboxylate(syn-isomer)

3-Acetoxymethyl-7β-(2-methoxyimino-2-phenylacetamido)-ceph-3-em-4-carboxylicacid (syn isomer) (5 g) and isonicotinamide (4.2 g) were mixed in water(150 ml) and acetone (30 ml.) and the suspension heated at 50° for 20hours. The mixture was cooled, filtered, evaporated to remove acetone,and the aqueous solution was passed down a column (3 × 16 cm.) of Dowex1 ion exchange resin in the acetate cycle. After washing the column withwater the eluate was freeze dried, and the resulting solid was stirredwith acetone (250 ml.) for 30 minutes, and the suspension filtered,producing the title compound (1.4 g.), [α]_(D) ²³ - 50° C (c 1.06 inDMSO), λ_(max). (pH 6 buffer) 260 nm. (ε 20,900), ν_(max) ^(Nujol) 1770(β-lactam), 1675 and 1560 (CONH) and 1605 cm.⁻¹ (CO₂ ⁻), τ (DMSO-d₆)values include 0.33, 1.49 (α, and β protons in pyridinium ring), 1.19and 1.74 (-CONH₂), 2.4-2.6 (multiplet, Ph), 0.26 (J, 8 Hz; NH), 6.10(singlet; OCH₃).

EXAMPLE 51 Sodium3-hydroxymethyl-7β-(2-methoxyimino-2-phenylacetamido)ceph-3-em-4-carboxylate (syn-isomer)

3-Acetoxymethyl-7β-(2-methoxyimino-2-phenylacetamido)ceph-3-em-4-carboxylicacid (syn-isomer) (2.0 g.) was dissolved in the minimum volume ofsaturated sodium bicarbonate solution and the solution was diluted withwater (160 ml) and warmed to 37°. Defatted wheat-gram (15 g) was addedand the mixture was stirred for 31/2 hours during which time the pHremained at 7.4. The mixture was then poured into acetone (200 ml) andfiltered through kieselguhr. The acetone was evaporated off underreduced pressure at 30° and the aqueous solution was covered with ethylacetate, taken to pH 2.7 by the addition of concentrated hydrochloricacid. The layers were separated and the aqueous layer was reextractedwith ethyl acetate. The combined ethyl acetate extracts were washed withwater. More water was added to the ethyl acetate solution and the pH wastaken to 7 by careful addition of 2N sodium hydroxide solution. Theorganic layer was further extracted with water and the combined aqueoussolution was washed with ethyl acetate and ether, degassed andlyophilised to give the title methoxime as a brown solid (1.52 g; 82%)[α]_(D) + 104° (c 1.1, DMSO) λ_(max). (pH 6 phosphate) 258.5 nm (ε14,100) ν_(max). (Nujol) 1730 (β-lactam), 1570 (COO⁻), 1640 and 1520cm⁻¹ (CONH), τ (D₂ O; 100 MHz) 2.2 to 2.6 (multiplet; aromatic protons),4.16 (doublet, J 4 Hz; C-7H), 4.79 (doublet, J 4 Hz; C-6H), 5.72(singlet; C-2 CH₂), 5.97 (singlet, NOCH₃), 6.32 and 6.59 (2 doublets(branches of quartet), J 18 Hz; C-3 CH₂).

EXAMPLE 523-Hydroxymethyl-7β-(2-benzyloxyiminothien-2'-ylacetamido)-ceph-3-em-4-carboxylicAcid (syn isomer)

To a suspension of3-acetoxymethyl-7β-(2-benzyloxyiminothien-2'-ylacetamido)ceph-3-em-4-carboxylicacid (1.0 g.) in water (50 ml.) was added sufficient saturated sodiumbicarbonate solution to dissolve the solid, and bring the solution to pH7.0. Defatted wheat germ (8.0 g.) was added to the solution, and themixture was stirred for 21 hr., keeping the pH at 6.8 to 7.0 by addingacetic acid. After 5 hr., the pH did not alter, and TLC (CHCl₃:MeOH:AcOH; 18:2:1) on an acidified aliquot showed reaction to be almostcomplete.

The mixture was filtered, and the pH of the filtrate was adjusted to pH4.5. Filtration through kieselguhr gave a yellow solution, whose pH wasadjusted to 2.5 under ethyl acetate. The aqueous mixture was extractedwith ethyl acetate, and the combined extracts were washed (water,brine), dried, and evaporated to dryness to give a brown solid.Trituration of this solid with methylene chloride gave a colourlesssolid (480 mg.), whose n.m.r. spectrum was consistent with that expectedof the hydroxymethyl compound.

A portion of the solid (366 mg.) dissolved in 50% aqueous ethanol (10ml.) was carefully neutralised with 0.1N sodium hydroxide solution (3.02ml., required). The ethanol was evaporated, and the aqueous mixture wasextracted thrice with ether. Evaporation of the aqueous solution gavesodium3-hydroxymethyl-7β-(2-benzyloxyiminothien-2'-ylacetamido)ceph-3-em-4-carboxylatedihydrate (132 mg.), [α]_(D) + 88° (c 0.89, DMSO), λ_(max). (pH 6phosphate buffer) 262 nm (ε 16,100) ν_(max). (Nujol) 1744 (β-lactam),1650 and 1522 (CONH), 1580 (CO₂ ⁻) cm.⁻¹, τ (DMSO-d₆) values include0.13 (doublet, NH), 2.54 (Ph) 4.76 (CH₂ Ph), 4.26 (quartet, 7-proton).

EXAMPLE 533-(2-Chloroethylcarbamoyloxymethyl)-7β-(2-methoxyiminophenylacetamido)ceph-3-em-4-carboxylicacid (syn-isomer)

A solution of3-hydroxymethyl-7β-(2-methoxyiminophenylacetamido)ceph-3-em-4-carboxylicacid (syn-isomer) (0.35 g.), 2-chloroethylisocyanate (0.097 g.) andtriethylamine (1.79 g.) in dimethylformamide (10 ml.) was stirred atroom temperature for two hours. The reaction mixture was poured intosaturated sodium bicarbonate solution, and the aqueous phase washed withethyl acetate, acidified and extracted with ethyl acetate. The combinedextracts were dried, concentrated to ca. 5 ml. and added dropwise withstirring to petroleum spirit (250 ml.). The resulting solid was filteredand dried to give the title acid (0.157 g., 35%) λ_(max). (pH 6 buffer)258 nm (ε 16,800), ν_(max). (Nujol) 3250 (NH), 2600 and 1715 (CO₂ H),1700 and 1530 (NHCO₂ R), 1660 and 1540 cm.⁻¹ (CONH), τ (DMSO-d₆) valuesinclude 0.22 (doublet J 9 Hz; 7β-NH), 2.3 to 2.6 (multiplet; aromaticprotons), 6.05 (singlet; OCH₃), 6.40 (multiplet; C-2 CH₂ and --CH₂ Cl),6.65 (multiplet; -NHCH₂).

EXAMPLE 54 (a) t-Butyl-3-acetoxymethyl-7β-(pyrid-4-ylacetamido)ceph-3-em-4-carboxylate

A suspension of pyrid-4-ylacetyl chloride hydrochloride (6.0 g.) inethyl acetate (50 ml) containing propylene oxide (12 ml.) was stirred,cooled in ice and treated dropwise with a solution of t-butyl3-acetoxymethyl-7β-aminoceph-3-em-4-carboxylate (5.0 g.) in ethylacetate (50 ml.). The mixture was stirred at 20° for 20 hours and thenwashed with saturated sodium bicarbonate solution and extracted with 2Nhydrochloric acid. The aqueous extract was washed with ethyl acetate,neutralised with saturated sodium bicarbonate solution and extractedwith ethyl acetate. The extract was washed with water, dried overmagnesium sulphate and evaporated to small bulk whereuponcrystallisation began. The crystalline solid was washed well withpetroleum spirit (bp. 40°-60°) and dried to give the title ester as abuff coloured powder (5.4 g., 80% based on amine). A portion (250 mg.)was recrystallised from ethyl acetate as white needles (170 mg.),[α]_(D) + 94° (c 0.9, DMSO) λ_(max). (EtOH) 256.5 nm (ε 9,900), ν_(max).(CHBr₃) 3412 (NH), 1784 (β-lactam), 1736 (OAc), 1722 (CO₂ R), 1690 and1512 cm.⁻¹ (CONH), τ (d₆ -DMSO) 0.81 (d, J 8 Hz; NH), 1.47 and 2.68 (2d,J 5 Hz; aromatic protons), 4.27 (q, J 8 and 5 Hz; C-7H), 4.85 (d, J 5Hz; C-6 H), 5.01 and 5.36 (2d, J 13 Hz; C-3CH₂), 6.38 (s; CH₂ CONH),6.39 (s; C-2H₂), 7.96 (s; OCOCH₃), and 8.50 (s; C(CH₃)₃).

(b) t-Butyl3-acetoxymethyl-7β-(2-hydroxyiminopyrid-4'-ylacetamido)-ceph-3-em-4-carboxylate

A solution of t-butyl3-acetoxymethyl-7β-(pyrid-4-ylacetamido)ceph-3-em-4-carboxylate (3.0 g.)in acetic acid (30 ml.) was stirred, cooled briefly in ice and treateddropwise over 3-4 minutes with a solution of sodium nitrite (1.38 g.),in water (10 ml.). The mixture was stirred at 20° for 30 minutes and wasthen diluted with water and extracted with ethyl acetate. The organicextract was washed with saturated sodium bicarbonate solution and waterand then dried over magnesium sulphate. Evaporation almost to drynessgave a residue which was dissolved in the minimum volume of acetone andadded dropwise to stirred petroleum spirit (bp. 40°-60°). The resultingsolid was collected, washed with petroleum spirit and dried to yield thetitle oxime as a white powder (2.9 g., 91%) which was shown (NMR) to bea syn-/anti-mixture (30:70).

The oxime mixture (2.5 g) was chromatographed on silica gel and elutedwith methanol-chloroform (1:49) to give the title compound(anti-isomer).

Further elution with methanol-chloroform (1:49) gave material which wasdissolved in acetone and added to stirred petroleum (bp. 40°-60°) toafford t-butyl3-acetoxymethyl-7β-(2-hydroxyiminopyrid-4'-ylacetamido)-ceph-3-em-4-carboxylate(syn-isomer, 0.81 g., 32% from mixture), [α]_(D) + 57° (c 1.11, DMSO),λ_(max). (EtOH) 253.5 nm (ε 17,600), ν_(max). (Nujol) 3220 (NH), 1784(β-lactam), 1744 (OAc), 1710 (CO₂ R) 1640 and 1526 cm.⁻¹ (CONH), τ (d₆-DMSO) -2.26 (s; NOH), 0.27 (d, J 8 Hz; NH), 1.33 and 2.47 (2d, aromaticprotons), 4.04 (q, J 5 and 8 Hz; C-7H), 4.71 (d, J 5 Hz; C-6H), 4.98 and5.33 (2d, J 13 Hz; C-3 CH₂), 6.20 and 6.53 (2d, J 18 Hz; C-2 H₂) 7.94(s, OCOCH₃), 8.49 (s, C(CH₃)₃).

(c) t-Butyl3-acetoxymethyl-7β-(2-methoximinopyrid-4'-ylacetamido)-ceph-3-em-4-carboxylate(syn-isomer)

A solution of t-butyl3-acetoxymethyl-7β-(2-hydroxyiminopyrid-4'-ylacetamido)-ceph-3-em-4-carboxylate(syn-isomer) (50 mg.), in tetrahydrofuran (10 ml.) was cooled to 0° andtreated with an excess of ethereal diazomethane. The mixture was stirredat ca. 5° for 45 minutes and then washed with water. The organic extractwas dried and evaporated to yield the title ester as a yellow foam (48mg., 93%), [α]_(D) + 55.5° (c 0.88, DMSO), λ_(max). (EtOH) 257.5 nm (ε16,580), ν_(max). (CHBr₃) 3390 (NH) 1784 (ε-lactam), 1736 (OAc), 1726(CO₂ R), 1684 and 1516 cm.⁻¹ (CONH), τ (d₆ -DMSO) 0.20 (d, J 8 Hz; NH),1.33 and 2.48 (multiplets; aromatic protons), 4.09 (q, J 5 and 8 Hz;C-7H), 4.74 (d, J 5 Hz; C-6H), 5.01 and 5.35 (2d, J 13 Hz; C-3CH₂), 5.99(s, NOCH₃), 6.38 (broad singlet; C-2H₂), 7.96 (s; OCOCH₃), 8.52 (s;C(CH₃)₃).

(d)3-Acetoxymethyl-7β-(2-methoxyiminopyrid-4'-ylacetamido)-ceph-3-em-4-carboxylicacid trifluoroacetic acid salt (syn-isomer)

A solution of t-butyl3-acetoxymethyl-7β-(2-methoxyiminopyrid-4'-ylacetamido)-ceph-3-em-4-carboxylate(syn-isomer) (0.35 g.) in trifluoroacetic acid (10 ml) was stood at 20°for 15 minutes. The solution was diluted with benzene and evaporated todryness to give a gum which was tritutated with ether to afford thetitle acid salt as a solid (0.26 g., 67%), [α]_(D) + 42° (c 0.45, DMSO),λ_(max). (pH 6 buffer) 255 nm (ε 19,000), ν_(max). (Nujol) 3250 (NH),2600 and 1720 (CO₂ H), 1778 (β-lactam), 1734 (OAc), 1666 (CF₃ CO₂ ⁻),1670 and 1520 cm.⁻¹ (CONH), τ (DMSO-d₆) 0.10 (d, J 8 Hz; NH), 1.23 and2.36 (multiplets; aromatic protons), 4.11 (q, J 5 and 8 Hz; C-7H), 4.76(d, J 5 Hz; C-6H), 4.98 and 5.29 (2d, J 13 Hz; C-3 CH₂), 5.97 (s;NOCH₃), 6.29 and 6.52 (2d, J 18 Hz; C-2H₂), 7.98 (s; OCOCH₃).

EXAMPLE 553-Acetoxymethyl-7β-[2-aminoethoxyimino(thien-2-yl)-acetamido]ceph-3-em-4-carboxylicacid, trifluoroacetate salt (syn isomer)

A solution of syn-(2-t-butoxycarboxamido)-ethoxyiminothien-2-ylacetylchloride (from the acid 314 mg) dissolved in acetone (10 ml.), was addeddropwise to an ice-cooled, stirred solution of 7β-aminocephalosporanicacid (272 mg.) in water (20 ml.) containing sodium bicarbonate (168mg.). The solution was stirred for two hours, then the acetone wasevaporated off. The aqueous mixture was acidified to pH 2.0 under ethylacetate, and extracted with ethyl acetate. The combined extracts werewashed (water, brine), dried, and evaporated to dryness to give3-acetoxymethyl-7β-[2-t-butoxy-carboxamidoethoxyimino(thien-2-yl)acetamido]ceph-3-em-4-carboxylic acid (540 mg.,95%), τ (DMSO-d₆) values include 0.27 (d, NH), 7.96 (s, OCOCH₃), 8.62(s, C(CH₃)₃).

This crude acid (500 mg.), was dissolved in trifluoroacetic acid (5ml.), and the solution was stood at room temperature for 5 min. and thenwas evaporated to dryness at room temperature. Dry benzene (25 ml.) wasadded to the residue, and the mixture was re-evaporated to dryness. Theoily residue was triturated with ether to give the title compound (346mg., 64%) as a colourless solid [α]_(D) + 39° (c 0.97 dioxan), λ_(max).(pH 6 phosphate buffer) 283 nm (ε 16,500), ν_(max). (Nujol) 1780 cm.⁻¹,τ (DMSO-d₆) values include 0.31 (doublet, J 8 Hz; NH), 1.98 (⁺ NH₃),4.08 (C-7 proton), 5.66 (--OCH₂), 6.8 (--CH₂ -N<), 7.96 (OCOCH₃).

EXAMPLE 56 7β-[2-t-butoxyimino-2-(benzo-[b]-thien-3-yl)acetamido]-3-(5-methyl-1,3,4-thiadiazol-2-yl)thiomethylceph-3-em-4-carboxylic acid(syn-isomer)

A solution of 2-(t-butoxyimino)-2-(benzo-[b]-thien-3-yl)-acetic acid(1.11 g) in methylene chloride (5 ml.) and dimethylformamide (1 ml) wasadded to a solution of diphenylmethyl7β-amino-3-(5-methyl-1,3,4-thiadiazol-2-yl)thiomethylceph-3-em-4-carboxylate(2.04 g) in methylene chloride (20 ml.). A solution ofdicyclohexylcarbodiimide (0.823 g) in methylene chloride (5 ml) wasadded to the above stirred solution at 20°. The mixture was kept at 5°for 16 hours and was then filtered. The filtrate was washed with 2Nhydrochloric acid, dilute sodium bicarbonate solution, water and brine,dried (MgSO₄) and concentrated under reduced pressure to give the crudediphenylmethyl ester of the title compound as an orange foam (3.37 g.).The foam was dissolved in anisole (6 ml) and the solution was treatedwith trifluoroacetic acid (25 ml.). After 5 minutes at 20° the solutionwas concentrated under reduced pressure. The residue was dissolved inethyl acetate and the resulting solution was again concentrated. Theresidue was then partitioned between ethyl acetate and dilute sodiumbicarbonate solution. The ethyl acetate layer was thoroughly extractedwith dilute sodium bicarbonate solution and the combined extracts werewashed with ethyl acetate and then were covered with ethyl acetate andtaken to pH 2 with concentrated hydrochloric acid. The layers wereseparated and the aqueous layer was extracted with ethyl acetate. Thecombined ethyl acetate extracts were washed with water and brine, driedand concentrated under reduced pressure to a low volume. The solutionwas then added dropwise to stirred petroleum (bp. 40°-60°, 400 ml) andthe precipitate was collected and washed with petroleum to give thetitle acid as a buff solid (1.0 g, 41%), [α]_(D) -87°(c 1 in DMSO)λ_(max). (pH 6 phosphate buffer) 277.5 nm (ε 16,850) ν_(max). (Nujol)include 1786 (β-lactam), 1672 and 1520 cm.⁻¹ (CONH) τ values (DMSO-d₆)include 0.27 (d, J 8 Hz; NH), 1.38 (m; H-4 benzo-[b]-thienyl) 1.86 (m;benzo-[b]-thienyl H-7), 2.15 (s; benzo-[b]-thienyl H-2) 2.44 (m;benzo-[b]-thienyl H-5 and H-6), 4.05 (dd, J 8 and 5 Hz; H-7), 4.72 (d, J5 Hz; H-6) 5.40 + 5.74 (2ds, J 13 Hz; C-3 CH₂), 6.13 + 6.37 (2ds, J 18Hz; C-2 CH₂), 7.29 (s; CH₃) and 8.57 (s; C(CH₃)₃).

EXAMPLE 577β-[2-Ethoxyimino-2-phenylacetamido]-3-(5-methyl-1,3-4-thiadiazol-2-yl)thiomethylceph-3-em-4-carboxylicacid (syn-isomer),

was prepared essentially as described in Example 56 (61% yield)[α]_(D) - 86° (c 1.1 in DMSO) λ_(max). (pH 6 phosphate) 262.5 nm (ε22,350) ν_(max). (Nujol) include 1780 (β-lactam) and 1664 and 1520 cm.⁻¹(CONH), τ values (DMSO-d₆) 0.21 (d, J 8 Hz; NH), 2.46 (m; aromaticprotons) 4.06 (dd, J 8 and 5 Hz; H-7), 4.73 (d, J 5 Hz; H-6), 5.40 +5.72 (2ds, J 14 Hz; C-3 CH₂), 5.74 (q, J 7 Hz; CH₃ CH₂ O) 6.11 + 6.39 (2ds, J 18 Hz; C-2 CH₂), 7.27 (s; CH₃ in thiadiazole) 8.68 (t, J 7 Hz; CH₃CH₂ O).

EXAMPLE 58

7β-[2-t-Butoxyimino-2-(thien-2-yl)acetamido]-3-(5-methyl-1,3,4-thiadiazol-2-yl)thiomethylceph-3-em-4-carboxylicacid (syn-isomer) was prepared as in Example 56 to give the acid (58%yield) [α]_(D) - 76° (c 1, DMSO) λ_(max). (pH 6 phosphate) 271 nm (ε14,400) ν_(max). (Nujol) include 1780 (β-lactam) and 1670 and 1530 cm.⁻¹(CONH), τ values (DMSO-d₆) include 0.276 (d, J 8 Hz; NH), 2.32 + 2.80(ms; thienyl protons), 4.08 (dd, J 8 and 5 Hz; H-7), 4.73 (d, J 5 Hz;H-6) 5.38 + 5.73 (2 ds, J 13 Hz; C-3 CH₂), 6.10 + 6.36 (2 ds, J 18 Hz;C-2 CH₂), 7.27 (s; CH₃) and 8.64 (s, C(CH₃)₃).

EXAMPLE 59 (a)t-Butyl-3-acetoxymethyl-7β-(2-ethoxyiminopyrid-4-ylacetamido)-ceph-3-em-4-carboxylate(syn-isomer)

A solution oft-butyl-3-acetoxymethyl-7β-(2-hydroxyiminopyrid-4-ylacetamido)-ceph-3-em-4-carboxylate(sny-isomer) (1.15g) in tetrahydrofuran (20 ml) was treated with anexcess of diazoethane at 20° for 40 minutes. The mixture was dilutedwith ether, washed with water and extracted with 2N-hydrochloric acid.The aqueous extract was neutralised with saturated sodium bicarbonatesolution and extracted with ethyl acetate. Evaporation of the driedorganic extract offered the title ester as a foam (0.84 g, 69%),[α]_(D) + 47° (c 0.84, DMSO), λ_(max). (EtOH) 259 nm (ε 15,450),ν_(max). (Nujol) 3300 (NH), 1788 (β-lactam), 1740 (OAc), 1724 (CO₂ R),1678 and 1540 cm.⁻¹ (CONH), τ (d₆ -DMSO) values include 0.12 (d, J 8Hz;NH), 1.26 and 2.42 (multiplets; aromatic protons), 5.69 (q, J 7Hz, OCH₂CH₃ ), 7.93 (s; OCOCH₃), 8.50 (s; (CH₃)₃) and 8.69 (t, J 7Hz; OCH₂ CH₃).

3-Acetoxymethyl-7β-(2-ethoxyiminopyrid-4-ylacetamido)-ceph-3-em-4-carboxylicacid trifluoroacetic acid salt (syn-isomer)

t-Butyl-3-acetoxymethyl-7β-(2-ethoxyiminopyrid-4-ylacetamido)-ceph-3-em-4-carboxylate(0.75 g) was deprotected with trifluoroacetic acid (10 ml) in the usualway to afford the title salt as a powder (0.61 g, 73%), [α]_(D) + 30° (c0.4, DMSO), λ_(max). (pH6 buffer) 257 nm (ε 12,800), ν_(max). (Nujol)3300 (NH), 2600 and 1720 (CO₂ H), 1782 (β-lactam), 1740 (OAc), 1680 (CF₃CO₂ ⁻), 1670 and 1552 cm.⁻¹ (CONH), τ (d₆ -DMSO) values include 0.06 (d,J 8Hz; NH), 1.20 and 2.28 (multiplets; aromatic protons), 5.65 (q, J7Hz; OCH₂ CH₃), 7.92 (s; OCOCH₃) and 8.64 (t. J 7Hz; OCH₂ CH₃).

EXAMPLES 60-65

The general procedures for the preparation of 3-substitutedmethyl-7β-(2-substituted oxyimino-2-arylacetamido)ceph-3-em-4-carboxylicacids described in Examples 19-46 were employed to prepare the compoundslisted in tabular form below. (the Table may be regarded as acontinuation of Table 2).

    __________________________________________________________________________     ##STR106##                                                                                                  pH 6      β-lactam                                                                       τ values for                                                              DMSO-d.sub.6                   Ex.                       [α].sub.D                                                                    λ.sub.max.                                                                       ν.sub.max. cm..sup.-1                                                            100 MHz     Yield              No. R         R.sup.a                                                                              Method                                                                             (dioxan)                                                                           nm    ε                                                                         (solvent)                                                                           x   R.sup.a                                                                            y  %                  __________________________________________________________________________    60  Ph        n-C.sub.4 H.sub.9                                                                    A    + 48°                                                                       257.5                                                                              19,900                                                                             1782  0.25                                                                             5.84, 8.2                                                                           4.09                                                                             92                                           (dioxan)       (Nujol)  8.8, 9.08                   61  Ph        n-C.sub.3 H.sub.7                                                                    A    +  49°                                                                      258  18,900                                                                             1778  0.26                                                                             5.89,                                                                               4.12,                                                                            82                                           (dioxan)       (Nujol)  9.07                        62  Ph        CH(CH.sub.3).sub.2                                                                   A    + 50°                                                                       258  18,400                                                                             1780  0.31                                                                             5.56,                                                                               4.08                                                                             73                                           (dioxan)       (Nujol)                              63                                                                                 ##STR107##                                                                             n-C.sub.3 H.sub.7                                                                    A    + 56° (dioxan)                                                              262.5 289 inf                                                                      16,000 11,200                                                                      1778 (Nujol)                                                                        0.17                                                                             5.90,                                                                               4.09, 9.06                                                                       82                 64                                                                                 ##STR108##                                                                             C.sub.2 H.sub.5                                                                      A    + 53° (dioxan)                                                              261.5                                                                              20,300                                                                             1786 (Nujol)                                                                        0.28                                                                             5.81,                                                                               4.15                                                                             95                 65                                                                                 ##STR109##                                                                             C.sub.2 H.sub.5                                                                      A    + 55.5° (dioxan)                                                            237 273 inf 303.5                                                                  12,900 15,500 23.600                                                               1785 (CHBr.sub.3)                                                                   0.03                                                                             571, 8.68                                                                           4.09                                                                             77                 __________________________________________________________________________

EXAMPLE 66 Sodium3-Acetoxymethyl-7β-(2-phenoxyimino-2-phenylacetamido)-ceph-3-em-4-carboxylate(syn isomer)

A solution of syn -2-phenoxyimino-2-phenylacetic acid (8.6g) in drymethanol (30ml) was neutralised with 1.105N sodium methoxide solution inmethanol (32.3ml). The methanol was evaporated, and the residual sodiumsalt (dried 48 hr. in vacuo over phosphorus pentoxide) was suspended indry benzene (75 ml) containing one drop of N,N-dimethylformamide. Thissuspension was treated with oxalyl chloride (4.5 ml), the mixture wasstirred for one hour, and then the solvent and excess reagent wereevaporated. A solution of the residual acid chloride in acetone (250 ml)was added over 30 min. to a stirred, ice-cooled solution of7β-aminocephalosporanic acid (9.71g) in water (500 ml) and acetone (250ml), containing sodium bicarbonate (6.5g). When addition was complete,the mixture was stirred for a further two hours, then the acetone wasevaporated under reduced pressure. The aqueous mixture was covered withether (500 ml) and acidified to pH 1.8; the acidic layer was furtherextracted with ether. The combined ether extracts were washed (water,saturated brine), dried and evaporated to dryness to givesyn-3-acetoxymethyl-7β-(2-phenoxyimino-2-phenylacetamido)ceph-3-em-4-carboxylicacid as a pale yellow foam (15.06g).

To a stirred solution of the above acid (14.5g) in acetone (150ml) wasadded (15 min) a solution of sodium 2-ethylhexanoate (5.5g) in acetone(50ml). The precipitated solid was collected, washed with acetone, anddried in vacuo to give the title compound (12.92g); [α]_(D) ²² + 111° (c1.13, DMSO); λ_(max). (pH 6 buffer) 260 nm (ε 19,400), ν infl. 285 nm (ε12,000); ν_(max). (Nujol) 3270 (NH), 1752 cm.⁻¹ (β-lactam); τ values(DMSO-d6) include -0.05 (d) (NH), 4.16 (dd) (7-H), 4.82 (d) (6-H), 7.97(s)(--O.COCH₃).

EXAMPLES 67-76 General Procedures for the Preparation of3-Acetoxymethyl-7β-(2-substitutedoxyimino-2-arylacetamido)-ceph-3-em-4-carboxylic Acids

Method A

A solution of the appropriate syn-2-substituted oxyimino-2-arylacetylchloride (prepared from 1 equiv. of the corresponding sodium salt withoxalyl chloride) was dissolved in acetone and the solution was addeddropwise to a stirred, cold (0°-5°) solution of 7β-aminocephalosporanicacid (1 equiv.) in water containing sodium bicarbonate (2-2.5 equiv.).The mixture was stirred for 0.5-2.5 hr. allowing the temperature to riseto room temperature. Acetone was removed by evaporation under reducedpressure, ethyl acetate was added, the pH was adjusted to 1.5-2.0 andthe product was extracted into ethyl acetate. The extracts were washedwith water and saturated brine, dried and evaporated to a foam or solid.

Method B

As in Method A but the product was extracted into ether.

Cephalosporin derivatives so prepared are listed in Table 5.

                                      TABLE 5                                     __________________________________________________________________________     ##STR110##                                                                                                pH 6   β-Lactam                             Ex.                     [α].sub.D                                                                    λ.sub.max.                                                                    ν.sub.max. cm..sup.-1                                                            τ values for DMSO-d.sub.6                                                 at 100 MHz       Yield              No.                                                                              R       R.sup.a Method                                                                             (dioxan)                                                                           nm ε                                                                         (solvent)                                                                           x    R.sup.a y   %                  __________________________________________________________________________    67                                                                                ##STR111##                                                                           Ph      A    + 72°                                                                       270.5 296                                                                        14,750 13,300                                                                     1780 (Nujol)                                                                        -0.14                                                                              2.4-2.8 4.04                                                                              95                 68                                                                                ##STR112##                                                                           Ph      A    + 68°                                                                       263.5 305                                                                        16,200 10,700                                                                     1778 (Nujol)                                                                        -0.14                                                                              2.4-2.8 4.01                                                                              96                 69                                                                                ##STR113##                                                                            ##STR114##                                                                           A    + 69°                                                                       275                                                                              16,800                                                                            1782 (Nujol)                                                                        0.33 5.28;8.0-8.6                                                                          4.16                                                                              98                 70                                                                                ##STR115##                                                                            ##STR116##                                                                           A    + 59°                                                                       262.5 294                                                                        15,700 12,300                                                                     1782 (Nujol)                                                                        0.26 5.25;8.0-8.6                                                                          4.10                                                                              95                 71                                                                                ##STR117##                                                                           C(CH.sub.3).sub.3                                                                     B    + 52.5°                                                                     235.5 273 301.5                                                                  13,100 17,000 24,300                                                              1780 (CHBr.sub.3)                                                                   0.20 8.62    4.04                                                                              93                 72 Ph                                                                                     ##STR118##                                                                           B    + 96° (Sodium salt in DMSO)                                                 260                                                                              19,800                                                                            1759 (Nujol) (Sodium salt)                                                          0.30 5.20;8.0-8.6                                                                          4.09                                                                              92                 73                                                                                ##STR119##                                                                           CH.sub.3                                                                              B    + 46°                                                                       267 293                                                                          13,000 12,300                                                                      1790 (CHBr.sub.3)                                                                  0.40 6.14    4.18                                                                              75                 74                                                                                ##STR120##                                                                           C(CH.sub.3).sub.3                                                                     B    + 56.5°                                                                     270                                                                              15,300                                                                            1790 (CHBr.sub.3)                                                                   0.56 8.69    4.15                                                                              79                 75                                                                                ##STR121##                                                                            ##STR122##                                                                           B    + 39.5°                                                                     237 266 295.5                                                                    17,500 13,400 14,700                                                              1786 (CHBr.sub.3)                                                                   0.34 4.75 2.36;2.81,2.96                                                                   4.18                                                                              79                 76                                                                                ##STR123##                                                                           CH.sub.3                                                                              B    + 39.5°                                                                     268.5 289                                                                        13,200 12,900                                                                     1792 (CHBr.sub.3)                                                                   0.30 6.18    4.15                                                                              76                 __________________________________________________________________________

EXAMPLE 773-(1-Methyltetrazol-5-ylthiomethyl)-7β-[2-phenoxyimino-2-phenylacetamido]-ceph-3-em-4-carboxylicacid (syn-isomer)

A suspension of 2-phenoxyimino-2-phenylacetic acid (464mg) in drymethylene dichloride (25ml) was added, over 5 minutes, to a stirredsolution of diphenylmethyl7β-amino-3-(1-methyltetrazol-5-ylthiomethyl)-ceph-3-em-4-carboxylate(989mg) and dicyclohexylcarbodiimide (454mg) in methylene dichloride(25ml). After stirring for a further 2 hours, the solvent was evaporatedin vacuo; the residue was suspended in ethyl acetate (60 ml), theinsoluble material filtered off, and the filtrate washed with saturatedsodium bicarbonate:water = 1:1, water, and brine (30 ml of each), dried,and evaporated to a foam (1.56g). A solution of this foam in benzene (10ml) was purified by chromatography on kieselgel (60g), withbenzene:ethyl acetate = 10:1 as eluant. Appropriate fractions werecombined and evaporated to dryness in vacuo to give diphenylmethyl3-(1-methyltetrazol-5-ylthiomethyl)-7β-[2-phenoxyimino-2-phenylacetamido]-ceph-3-em-4-carboxylate(syn-isomer) as an orange foam (1.16g, 87%). A solution of this foam ina mixture of trifluoroacetic acid (4ml) and anisole (1ml) was kept at23° for 5 minutes, and the solvents were removed at 40° (2mm). Theresidue was suspended in ether (80 ml), saturated sodiumbicarbonate:water = 1:3 (120ml) was added, and the mixture was stirreduntil all the solid had dissolved (ca. 10 minutes). The aqueous phasewas separated, covered with ethyl acetate (150 ml), and acidified to pH2 with 2N-hydrochloric acid. The organic phase was separated, washedwith water, and brine (50ml of each), and the solvent evaporated invacuo. The residue was dissolved in acetone (50ml), the solution stirredfor 5 minutes with charcoal (ca. 1g), and the mixture filtered through apad of kieselguhr. The filtrate was dried and evaporated to a foam(780mg), which was dissolved in ethyl acetate, and the solution run intopetroleum ether to give the title acid as a colourless, amorphous solid(640mg, 63.3%); [α]_(D) ²³ - 64° (c, 1.01, acetone); λ_(max). (0.1 M -pH 6 phosphate buffer) 261 nm. (ε 19,200); τ (DMSO-d6) values include-0.11 (NH, d, J 8 Hz.), 4.00 (7-H, dd, J 5 and 8 Hz.), 4.70 (6-H, d, J 5Hz), and 6.04 (CH₃ -).

EXAMPLES 78-93 General Procedures for the Preparation of7β-(2-substitutedoxyimino-2-arylacetamido)-3-(substituted)-ceph-3-em-4-carboxylic acidsusing Dicyclohexylcarbodiimide

(i) To a solution of a t-butyl (Example 93) or diphenylmethyl ester of7β-amino-3-(substituted)-ceph-3-em-4-carboxylic acid (1 equiv.) anddicyclohexylcarbodiimide (1-1.2 equiv.) in dry methylene chloride wasadded at 0°-20°, a solution of the syn-2-alkoxy- or2-aryloxyimino-2-arylacetic acid (1 equiv.) in dry methylene chloride.After stirring for 45 min. -3hr. at room temperature the mixture wasfiltered and the filtrate was evaporated to dryness. The residue inethyl acetate was washed successively with sodium bicarbonate solution,water and brine. The organic phase was dried and evaporated to a foam orsolid. The resulting ester was purified by crystallisation orchromatography on silica and characterised by p.m.r. and thin layerchromatography.

Where the 7β-amino starting material was available as its p-toluenesulphonic acid salt (Example 92) the free base was liberated by shakingwith ethyl acetate and an excess of saturated sodium bicarbonatesolution. After washing with water and brine the organic layer wasevaporated to dryness and the free amine was redissolved in methylenechloride.

(ii) The intermediate esters so derived were deprotected by dissolvingin a mixture of trifluoracetic acid (3-10 ml/1g of ester) and anisole(1-5ml/1g of ester) and left at room temperature for 5-10 min. when thesolvents were removed by evaporation under reduced pressure. The crudeacid was shaken with ether or ethyl acetate and an excess of aqueoussodium bicarbonate and the aqueous layer was washed with ethyl acetate.The aqueous phase was separated, covered with ethyl acetate andacidified to pH 1-2 with 2N-hydrochloric acid. The organic layer waswashed, dried and evaporated to give the required syn-7β-(2-alkoxy-or2-aryloxy-2-arylacetamido)-3-(substituted)-ceph-3-em-4-carboxylic acid,the compounds so obtained being listed in Table 6.

(iii) Diphenylmethyl7β-Amino-3-(1-ethyltetrazol-5-ylthiomethyl)-ceph-3-em-4-carboxylate(used as Starting Material for Example 79)

(a) Diphenylmethyl3-(1-ethyltetrazol-5-ylthiomethyl)-7β-(2-thienylacetamido)-ceph-3-em-4-carboxylate

A solution of diphenylmethyl3-bromomethyl-7β-(2-thienylacetamido)-ceph-3-em-4-carboxylate (11.67g)and 1-ethyltetrazoline-5-thione (2.6g) in dry tetrahydrofuran (150ml)was stirred at 0° and a solution of triethylamine (2.8ml) intetrahydrofuran (25ml) was added, dropwise, over 5 minutes. Theresulting suspension was stirred for a further 25 minutes, during whichtime the temperature was allowed to rise to ca. 20°, and was then added,over 5 minutes, to a stirred mixture of 2N-hydrochloric acid (50ml),water (350ml), brine (350ml), and ethyl acetate (600ml). The organicphase was separated, and washed with 2N-hydrochloric acid, saturatedsodium bicarbonate, water, and brine, and dried and evaporated to a foam(11.71g). A solution of this foam in benzene (25ml) was purified bychromatography on kieselgel (200g), with benzene:ethyl acetate = 5:1 aseluant. Appropriate fractions were combined and the solvents evaporatedin vacuo. The residue was dissolved in methylene dichloride, and thesolution run into petroleum ether to give the ester as a pale-yellow,amorphous solid (8.585g, 68 %); [α]_(D) ²³ -131° (c 0.97, CHCl₃);λ_(max). (EtOH) 264 nm (ε 7,300), τ (CDCl₃) values include 4.12 (7-H,dd, J 5 and 9 Hz.), 5.04 (6-H, d, J 5 Hz.), 5.83 (CH₃ CH₂ -, q, J 7Hz.), and 8.57 (CH₃ CH₂ -, t, J 7 Hz.).

(b) A solution of pyridine (2.13ml) in dry methylene dichloride (10ml)was added, over 5 minutes, to a stirred suspension of phosphoruspentachloride (5.47g) in methylene dichloride (20ml). After 10 minutes,the suspension was cooled to 0°, and a solution of diphenylmethyl3-(1-ethyltetrazol-5-yl-thiomethyl)-7β-(2-thienylacetamido)-ceph-3-em-4-carboxylate(8.3g) in methylene dichloride (40ml) was added, dropwise, over 10minutes. The resulting solution was stirred for a further 1 hour, duringwhich time the temperature was allowed to rise to ca. 23°, and thenadded, over 10 minutes, to a stirred and cooled (0°) mixture of methanol(30 ml) and methylene dichloride (60ml). After 15 minutes,N-hydrochloric acid (50ml) was added, and stirring continued for afurther 10 minutes. The organic phase was separated, stirred for 30minutes with saturated sodium bicarbonate (200ml), and washed withsaturated sodium bicarbonate and brine and treated with some charcoal.The suspension was filtered through a kieselguhr pad, the filtrate driedand evaporated to an oily solid (7.47 g). This material was trituratedwith ethyl acetate (15ml) to give the amine as a pale-yellow solid(3.854g, 58%); [α]_(D) ²³ -213° (c 1.14, CHCl₃); λ_(max). (CHCl₃) 265nm.(ε 7,900); 268.5 nm. (ε 7,900) and 279.5nm (ε 7,800); τ (DMSO-d6) valuesinclude 4.92 (d, J 5 Hz.) and 5.11 (d, J 5 Hz.), (6-H and 7H), and 5.72(q, J 7 Hz.) and 8.61 (t, J 7 Hz.), (CH₃ CH₂ --).

(iv) Diphenylmethyl7β-Amino-3-(6-nitrobenzothiazol-2-ylthiomethyl)-ceph-3-em-4-carboxylate,hydrochloride (used as Starting Material for Examples 81 and 85).

A solution of diphenylmethyl3-bromomethyl-7β-formamidoceph-3-em-4-carboxylate, 1β-oxide (10.068g)and 2-mercapto-6-nitrobenzothiazole (4.244g) in dryN,N-dimethylformamide (125ml) was stirred at 0°; a solution oftriethylamine (3.2ml) in N,N-dimethylformamide (25ml) was added,dropwise, over 5 minutes, and stirring continued for a further 2 hours,during which time the temperature was allowed to rise to ca. 23°. Thesolvent was removed at 40°(2mm.); the residue was partitioned betweenmethylene dichloride (300ml) and water (300ml), and the organic phasewashed with 2N-hydrochloric acid, water, and brine and dried andevaporated to a foam (14.35g). A solution of this foam in dry methylenedichloride (200ml) was stirred at -20°, a solution of phosphorustribromide (2.5ml, ca 1.5 equiv.) in methylene dichloride (25 ml) wasadded, dropwise, over 5 minutes, and stirring continued for a further 30minutes at -10° to -15°. The resulting solution was stirred for 30minutes with saturated sodium bicarbonate (250ml); the organic phase wasseparated, and washed with saturated sodium bicarbonate and brine andtreated with some charcoal. The suspension was filtered through akieselguhr pad, and the filtrate dried and evaporated to a foam(10.71g). A suspension of this foam in methanol (200ml) was stirred at0°; phosphorus oxychloride (3.66 ml - 2 equivs.) was added, over 2minutes, and stirring continued for a further 2 hours at ca. 23°, duringwhich time the solid all dissolved. The solvent was evaporated off;ethyl acetate (100ml) was added, and the resulting suspension evaporatedto dryness in vacuo. The residual gum was dissolved in methylenedichloride (100ml); the solution was stirred at 0° and ether (300 ml)was added, over 5 minutes. The precipitate was filtered off, and washedwith ether (100ml), and dried in vacuo to give the hydrochloride aspale-yellow flakes (9.744g, 78%); [α]_(D) ²³ - 94° (c 1.0, DMSO);λ_(max). (EtOH) 328nm. (ε 13,400); τ (DMSO-d6) values include 4.72 (6Hand 7-H), 5.10 and 5.57 (3-CH₂, q, J 14 Hz.), and 6.10 (2 CH₂).

(v) Diphenylmethyl7β-Amino-3-(6-nitrobenzothiazol-2-ylthiomethyl)-ceph-3-em-4-carboxylate

A solution of the hydrochloride described above (910mg) in methylenedichloride (50ml) was stirred for 30 minutes with saturated sodiumbicarbonate (50ml). The organic phase was separated, and washed withsaturated sodium bicarbonate and brine and treated with some charcoal.The suspension was filtered through a kieselguhr pad, and the filtratedried and evaporated to a foam (660mg). This material was digested withmethanol (50ml) to give the amine as a pale-yellow solid (432mg, 50%);[α]_(D) ²⁰ - 195° (c 1.01, CHCl₃); λ_(max). (CHCl₃) 251 nm. (ε 14,500)and 334 nm. (ε 16,800); τ (CDCl₃) values include 5.04 and 5.22(doublets, J 5 Hz., 6-H and 7-H), and 7.96 (NH₂).

    TABLE 3      ##STR124##         pH 6 β                                                         l     actam τ      values for DMSO-d6 at  Ex.  [α].sub.D λ.sub.max. ν.sub.m     ax. 100 MHz Yield* No. R R.sup.a Y (acetone) nm ε (Solvent) x     R.sup.a Y %                   78      ##STR125##     C(CH.sub.3).sub.3      ##STR126##      -89° 268.5 15,900 1786(Nujol) 0.26 8.69 6.05(CH.sub.3) 57 79      ##STR127##      C(CH.sub.3).sub.3      ##STR128##      -96° 268.5 18,200 1782(Nujol) 0.36 8.67 5.66;8.56(C.sub.2     H.sub.5) 19 80      ##STR129##      C(CH.sub.3).sub.3      ##STR130##      -110° 279 31,800 1788(CHBr.sub.3) 0.27 8.70 2.0;2.36(Ph) 81      ##STR131##      C(CH.sub.3).sub.3      ##STR132##      -178° 293.5(EtOH) 20,200 1780(Nujol) 0.33 8.72 0.931.67;1.97(Ar)     32 82      ##STR133##      C(CH.sub.3).sub.3      ##STR134##     -95° 277.5 21,200 1780(Nujol) 0.32 8.69 6.05(CH.sub.3) 35 83      ##STR135##      ##STR136##      ##STR137##      -78° 271 18,100 1782(Nujol) 0.30 5.22;8.25 6.00(CH.sub.3) 59 84      ##STR138##      ##STR139##      ##STR140##     -80° 279 22,300 1780(Nujol) 0.29 5.22;8.27 6.0(CH.sub.3) 46 85      ##STR141##      ##STR142##      ##STR143##      -153° 280.5 17,400 1780(Nujol) 0.30 5.25;8.30 0.91,1.64and1.95(Ar     ) 24 86 Ph C.sub.2      H.sub.5     ##STR144##      -93° 262 19,600 1782(Nujol) 0.24 5.79;8.72 6.05(CH.sub.3) 48 87      ##STR145##      C(CH.sub.3).sub.3 CHCH.sub.2 -47° 292(EtOH) 17,200 1764(CHBr.sub.     3) 0.29 8.66 2.754.684.9 54 88 Ph C.sub.2 H.sub.5 CHCH.sub.2 -77°     276 19,200 1782 0.19 5.78; 3.01 47        (CHBr.sub. 3)8.704.35      4.64 89      ##STR146##      C(CH.sub.3).sub.3 CHCH.sub.2 -49°  232287.5297(EtOH) 24,90019,8001     8,900 1764(CHBr.sub.3) 0.32 8.57 2.754.694.93 60 90      ##STR147##      C(CH.sub.3).sub.3 CH.sub.2 OCOCHCHCH.sub.3 +44°(DMSO) 260 15,000 1     788(Nujol) 0.32 8.70 3.04;4.078.14 50 91 Ph C.sub.2 H.sub.5 CH.sub.2     SCOCH.sub.3 -64° 260 18,600 1780 0.27 5.78 7.6464 (DMSO) (Nujol)8.     73 (CH.sub.3) 92      ##STR148##      C(CH.sub.3).sub.3 CH.sub.2      OCOCHCHCH.sub.3 +37.5°(DMSO) 231.5(EtOH) 27,200 1790(Nujol) 0.28     8.56 3.0;4.058.12 43 93 Ph CH.sub.2 CO.sub.2 H CH.sub.2 OCOCH.sub.3     +40° 257 17,100 1780 0.26 5.30 7.96 32(dioxan)(Nujol)(CH.sub.2)(CH     .sub.3)     *Yields are given as overall yields for the coupling and deprotection     reactions [ stages (i) and (ii) above].

EXAMPLE 943-(5-Methyl-1,3,4-thiadiazol-2-yl)thiomethyl-7β-[2(then-2-yl)oxyimino-2-(thien-2-yl)-acetamido]-ceph-3-em-4-carboxylicacid (syn-isomer)

A solution of syn-then-2-yloxyiminothien-2-ylacetic acid (715 mg) inmethanol (20 ml) was neutralised with 0.32 N sodium methoxide solution(8.7 ml). The solvent was removed in vacuo, and the residual sodium saltdried by azeotroping with benzene (2 × 20 ml). Oxalyl chloride (685 mg)was added to a suspension of the above salt in benzene (30 mg)containing N,N-dimethylformamide (1 drop). The resulting solution wasstirred at 20° for 1.5 hr, and evaporated to dryness in vacuo to givethe acid chloride.

A solution of this acid chloride in acetone (20 ml) was added dropwiseto a stirred solution of7β-amino-3-(5-methyl-1,3,4-thiadiazol-2-yl)-thiomethylceph-3-em-4-carboxylicacid hydrochloride (1.00 g) in water (30 ml) containing sodiumbicarbonate (660 mg), at 0°. The mixture was stirred for 2 hr. andallowed to reach room temperature. The acetone was removed in vacuo andthe solution acidified to pH 1.9. The solution was extracted with ethylacetate (6 × 70 ml) and the combined extracts were washed with water,dried and evaporated to dryness. The crude product was washed withbenzene cyclohexane (1:1, 2 × 20 ml) and cyclohexane and dried to givethe title carboxylic acid (863 mg) [α]_(D) - 61° (c 1.44, DMSO),λ_(max). (pH 6 buffer) 239 nm (ε 17,900), 273 nm (ε 19,150), ν_(max).(Nujol) 1784 cm⁻¹ (β-lactam) τ (DMSO-₆) values include 0.09 (d, NH),4.68 (s, CH₂ -thienyl), 7.31 (s, CH₃).

The sodium and potassium salts of the compounds of the Examples areprepared in conventional manner by reaction with sodium or potassium2-ethylhexanoate respectively. To illustrate such salt preparation theformation of sodium3-acetoxymethyl-7β-(2-methoxyimino-2-phenylacetamido)ceph-3-em-4-carboxylate(syn-isomer is described in more detail below.

EXAMPLE 95

Syn-3-acetoxymethyl-7β-(2-methoxyimino-2-phenylacetamido)ceph-3-em-4-carboxylicacid (10.84 g.), was dissolved in the minimum amount of ethyl acetate(280 ml.) and a 1M solution of sodium ethyl hexanoate (25 ml.) was addeddropwise to the stirred solution, which was stirred for 20 minutes, andcooled at 0° for 2 hours. The precipitated salt was removed byfiltration, and stirred with ethyl acetate (100 ml.) for 2 hours, andthe solid (9.6 g.) filtered, washed and dried. This was then stirredwith ether (2 × 200 ml.) at room temperature for 30 minutes, producingthe title compound (8.9 g., 78%), [α]_(D) ²² + 60° (c, 1.06 in water),λ_(max). (pH 6 buffer) 258-259 nm (ε 19,150).

The following example illustrates the preparation of an amine base salt,such salts otherwise being prepared conveniently from the appropriateamine.

EXAMPLE 96 Diethanolammonium3-Acetoxymethyl-7β-(2-phenoxyimino-2-phenylacetamido)-ceph-3-em-4-carboxylate(syn-isomer)

To a stirred solution of crudesyn-3-acetoxymethyl-7β-(2-phenoxyimino-2-phenylacetamido)ceph-3-em-4-carboxylicacid (prepared as in Example 66) (5.94g) in 2-propanol (30ml) was addeda solution of diethanolamine (3.8ml) in 2-propanol (8ml). Theprecipitated solid was collected, washed (2-propanol, then ether), anddried in vacuo to give the title compound (3.43g), m.p. 139.5°; τ values(DMSO-d6) include -0.06 (d) (NH), 4.13 (dd) (7-H), 4.78 (d) (6-H), 6.96and 7.96 (--CH₂ --CH₂ --).

The following Examples illustrate the formulation of pharmaceuticalpreparations.

EXAMPLE A Dry Powder for Injection

Sterile sodium3-acetoxymethyl-7β-(2-methoxyimino-2-phenylacetamido)ceph-3-em-4-carboxylate(syn-isomer) powder is filled into glass vials so that the glass vialscontain 500 mg. and 1.0 g of the antibiotic as desired. Filling iscarried out aseptically under a blanket of nitrogen. The vials areclosed using rubber discs held in position by aluminium sealing rings,thereby preventing gaseous exchange or ingress of micro-organisms. Theproduct is intended for reconstitution with water for injections orother suitable sterile vehicle shortly before administration.

EXAMPLE B

    ______________________________________                                        Intramammary Infusion for Cattle                                              ______________________________________                                        Percentage composition (w/w)                                                  Sodium 3-acetoxymethyl-7β-(2-ethoxyimino-                                2-phenylacetamido)-ceph-3-em-4-carboxylate                                    (syn-isomer)               10.00                                              Vehicle to:                100.00                                             Vehicle:   Tween 60            3.00                                                      White Beeswax       6.00                                                      Arachis Oil         91.00                                          ______________________________________                                    

The last three ingredients are heated together at 150° C for one hourand then cooled to room temperature with stirring. The sterileantibiotic powder is added aseptically to this vehicle and the productrefined with a high speed stirrer. The preparation is filled asepticallyinto sterile collapsible aluminium tubes so that each tube contains 3.0g of the preparation comprising 300 mg. of the cephalosporin derivative.

EXAMPLE C

    ______________________________________                                        Dry Blend for an Oral Syrup                                                   ______________________________________                                        Sodium 3-acetoxymethyl-7β-(2-methoxyimino-                               2-thien-2'-ylacetemido)ceph-3-em-4-                                           carboxylate (syn isomer)   5.00 g.                                            Sodium Saccharin           0.10 g.                                            Sodium Citrate (anhydrous) 1.00 g.                                            Citric Acid (anhydrous)    0.10 g.                                            Amaranth                   0.01 g.                                            Spray-dried Raspberry Flavour                                                                            1.00 g.                                            Sucroseto                  75.00 g.                                           ______________________________________                                    

The product is intended for reconstitution with sufficient purifiedwater to give a final volume of 100 ml., which should all beadministered within a few days, each 5 ml. dose of syrup containing 250mg. of the cephalosporin derivative.

In order to prepare the blend, the amaranth is intimately mixed withsome of the sodium citrate and milled. The sodium saccharin and citricacid are blended together. They are mixed thoroughly with the colourtriturate, then with the remainder of the sodium citrate, flavour andantibiotic powder in that order. This blend is milled, mixed withsucrose and then 75 g. is filled into each of a number of 150 ml.capacity bottles, which are closed with moisture-proof screw caps.

EXAMPLE D (a) Oral Capsules

Sodium3-acetoxymethyl-7β-(2-ethoxyimino-2-phenylacetamido)ceph-3-em-4-carboxylate(syn-isomer) is blended with one percent magnesium stearate and filledinto size 0 hard gelatin capsules, each capsule containing a claimeddose of 250 mg. of the cephalosporin antibiotic. The capsules are packedin glass vials with plastic caps giving a moisture-proof seal.

We claim:
 1. A compound selected from the group consisting of a highlyactive cephalosporin antibiotic highly stable to β-lactamases, havingthe formula ##STR149## wherein R^(u) is phenyl or naphthyl or each ofthese groups substituted by a chloro, bromo, iodo, fluoro, hydroxy,lower alkyl, nitro, amino, loweralkylamino, diloweralkylamino, loweralkanoyl, lower alkanoylamino, lower alkoxy, lower alkylthio orcarbamoyl;R^(b) is lower alkyl or cycloalkyl of 3-7 carbon atoms; Y is agroup of formula -SW where W is thiadiazolyl,5-methyl-1,3,4-thiadiazol-2-yl, diazolyl, triazolyl, tetrazolyl,1-methyltetrazol-5-yl, thiazolyl, thiatriazolyl, oxazolyl, oxadiazolyl,2-phenyl-1,3,4-oxadiazol-5-yl, benzimidazolyl, benzoxazolyl,triazolopyridyl, benzothiazolyl, nitrobenzothiazolyl, purinyl, pyridyl,pyrimidyl or an alkyl group of 1-4 carbon atoms, said cephalosporinantibiotic being in the form of a syn isomer free of the correspondinganti isomer to the extent of at least 75% based on the total weight ofsaid antibiotic; and a physiologically acceptable salt thereof.
 2. Thecompound of claim 1 which is3-methylthiomethyl-7β-(2-methoxyimino-2-phenylacetamido)-ceph-3-em-4-carboxylicacid (syn isomer).
 3. The compound of claim 1 which is7β-(2-ethoxyimino-2-phenylacetamido)-3-(5-methyl-1,3-4-thiadiazol-2-yl)thiomethyl-ceph-3-em-4-carboxylic acid (syn isomer).
 4. The compound ofclaim 1 which is7β-(2-ethoxyimino-2-phenylacetamido)-3-(1-methyltetrazol-5-yl)thiomethylceph-3-em-4-carboxylicacid (syn isomer).